^ 'S**-^^*^8S G> X\ *:,- -cr-lffi::*^ 5 ! % o> 1 : 3- i P- _D i-=l a. a a m a V T Of. - i . ' REPORT ON THE MARINE ISOPODA OF NEW ENGLAND AND ADJACENT WATERS. BY OSCAR HAKGER. [FROM THE REPORT OF THE UNITED STATES COMMISSIONER OF FISH A.N-J FISHERIES, PART VI, FOR 1878.] XIV. REPORT ON THE MARINE ISOPODA OF NEW ENGLAND AND ADJACENT WATERS. BY OSCAR UARGER. The following paper includes the species of Isopoda at present known to inhabit the coast of New England and the adjacent regions, as far as Nova Scotia on the north and New Jersey on the south. These limits have been chosen from the fact that nearly all the marine collections of this order made by the Fish Commission have been from the New Eng- land coast, except those from the Nova Scotia coast in 1877, while the commission had its headquarters at Halifax. Previous to the work of the Fish Commission extensive collections had also been made, mostly by Professors A. E. Yerrill and S. I. Smith, of Yale College, in the Bay of Fundy and at other places along the coast as far south as Great Egg Har- bor, in the southern part of New Jersey. The collections thus obtained, and others in the museum of Yale College, have, through the kindness of Professor Yerrill, been used in the preparation of this article. As there has not yet been sufficient opportunity for the study of the Bopi/ridce, only a list of the known species of that family is included, and for this I am indebted to Professor S. I. Smith. The species of the remaining fam- ilies are described at length, and nearly all figured in more or less detail in the plates accompanying the article. Throughout the article especial reference will be had to the Isopoda of our own coast, and many pecu- liarities of structure, not found in our genera, will be more or less com- pletely disregarded. As the Oniscidce are a terrestrial family, only a few species, found usually, or only, along the shore are here included. ISOPODA. This group is an order of Crustacea, so named from two Greek words, "), are in general of a delicate texture, and three-lobed at the tip, the two outer lobes being articulated to the basal piece, and all three lobes cili- ated on their inner margins. The inner, or first pair of maxillae are of a less delicate texture than the outer, and are hardly of the ordinary form in Cirolana (pi. X, fig. 61 c) ; reference may, therefore, be made to Synidotea nodulosa (pi. VI, fig. 35 c), where the two unequal lobes are shown, the inner comparatively small, and supported on a slender pe- duncle, curved inward, truncated at the tip, and bearing stout, curved, pectinated setae; the outer much more robust and larger, similar in general outline to the inner, but armed with stout, curved, denticulated spines at the tip. The mandibles (pi. X, fig. 61 d) are usually toothed at the apex, the teeth being supported 011 a dentigerous lamella, which may be double on one mandible, usually the left, and receive the lamella of the oppo- site mandible between the two ; below this lamella is often a comb of pectinate seta3, and, generally, a molar process, as in Janira alta (pi. Ill, fig. 12 &, TO). In many genera a three-jointed palpus (pi. X, fig. 61 d, p) is articulated to the external surface of the mandible, and, usually, the terminal segment of the palpus is more or less semicircular, or curved, and bears on its inner margin a very regular comb of setae (pi. Ill, fig. 12 &), apparently of service in cleansing the organs of the mouth. This comb may be continued or repeated on the second segment, as in Ciro- lana (pi. X, fig. 61 d, p). In the " sow-bug" and many other genera the 300 REPORT OF COMMISSIONER OF FISH AND FISHERIES. mandibles arc destitute of palpi. The oral opening between the mandi- bles is defended by an upper and lower lip, or labrum and labium, which are, however, median, and not paired organs, like the other parts of the mouth. The seven thoracic segments are of firm texture above, but softer underneath. The dorsal surface is in general more or less rounded, and in Cirolana is continued well down at the sides, where, except in the first segment, it is crossed by a suture cutting off a quadrate, or somewhat triangular piece, called an epimeron, or, in the plural, the epimcra. The ^pimera are well shown in the side view of Cirolana concharum (pi. IX, fig. 58). They belong to the legs, and form a portion of the large prox- imal segment called the coxa. Usually, however, the legs are figured as in pi. X, fig. G2 Z>, without this segment, which adheres strongly to the body; often, as in the first segment of Cirolana, the suture sep< arating it disappears. The remaining six segments of the legs are more slender, and are called respectively, beginning with the segment follow- ing the coxa, the basis, ischiurn, merus, carpus, propodus, and dactylus, the last being usually slender and curved, often bearing a curved spine or claw at the tip, and, especially in the first pair, capable of flexion on the propodus, so as to form a prehensile hand. In the Tanaidce, as in many of the higher Crustacea, the propodus may be prolonged into a digital process, against which the dactylus closes, forming a chela (pi. XIII, fig. 85), or chelate hand, as in the lobster. In the ^gid(c and the Cymothoidce a greater or less number of the dactyli are strongly curved or hooked, for the purpose of retaining firm hold of the host, on which these parasitic species live. Legs thus constructed are called ancoral, as in Livoneca ovalis (pi. XI, fig. 67 d and e). Of the seven parrs of legs attached to the thorax or pereion, the first three have in general a resemblance to each other, and are often more or less prehensile, while, as in Chiridotea (pi. IV, figs. 16 and 20), the last four are more strictly locomotive organs; but to this condition of things there are many exceptions, especially in the development of the first pair of legs, which are quite variable throughout the order, be- ing not even pediform in the males of the GnatMidce, but two-jointed, in our species, and lamelliform (pi. XII, fig. 76 d). Except in this family, however, no confusion arises from speaking of the thoracic appendages as the first to the seventh pair of legs, or thoracic legs, and in general these terms will be used except where it may be necessary to use the technical terms, gnathopods or gnathopoda and pereiopods or pereiopoda, for these organs, as proposed by Spence Bate, according to whose system the first and second pairs are called the first and second pairs of gnathopoda* or gnathopods, and the remaining five pairs the first to the fifth pair of pereiopoda or pereiopods. When necessary these terms will be added as explanatory, having the inerit of scientific accuracy as well as applicability to other groups of Crustacea, where a * See also Edwards, Aim. Sci. uat., Ill, tonie xvi, p. 221-291. MARINE ISOPODA OF NEW ENGLAND, ETC. 301 marked distinction of structure and function frequently occurs between the organs homologous with the second and third pairs of legs in the Isopoda. In the adult females of this order there is commonly formed, on more or less of the under surface of the thorax, an incubatory pouch for the reception and development of the eggs. The outer surface of the pouch is usually formed by four pairs of lamellae attached just within the origins of the second, third, and fourth, together with the first or fifth pairs of legs, and in the females of many genera, Sphccwma and Asellus for instance, these lamellae may be observed in a rudimentary condition on the under surface of the thorax- when not actually in use carrying eggs or young. In Asellus, and in some other genera, they are found upon the first to the fourth segments, instead of the second to the fifth. In Antliura the incubatory pouch extends over only three seg- ments, the third, fourth, and fifth ; and in Astacilla it is confined to a single segment, being composed of a single pair of elongated plates attached to the fourth segment. In Tanais a further remarkable va- riation occurs, and the eggs and young are carried in sacs attached to the under surface of the fifth thoracic segment, while in the closely allied genus Leptochelia the form of the incubatory pouch is normal. In the Gnathildce and Anihuridas, according to Speuce Bate and Dohrn, the incubatory pouch is formed by the splitting of the integument of the inferior surface of the thoracic segments in the females, and for the dis- charge of the young the outer lamella thus formed further divides into scales, one pair for each segment of the pouch. In <7?ra, Epelys^ and probably other genera, a similar mode of development seems to occur. The six segments of the pleon are smaller than those of the thorax, often much smaller, and frequently more or less united, sometimes consolidated into a single piece with scarcely any trace of division above, but the number of pairs of appendages is generally six, show- ing the composite nature of the apparently simple organ. Of these six pairs of appendages or pleopods, the first five are more or less con- cealed beneath the pleon, and consist on each side of a basal segment bearing two lamellae (pi. IV, fig. 19 c), of which the outer is the anterior when they overlap. These lamella?, at least the anterior pairs, are usually ciliated along more or less of their distal margins with long slender plumose setre. In the males of most of the genera, the inner lamella of the second pair bears, articulated near the base of its inner margin, a slender stylet (pi. IV, fig. 19 6, s). This stylet seems to afford, in many cases, specific and even generic characters. The last segment, sometimes called the telson, has its pair of append- ages specially modified, and called the uropods (pi. X, fig. 63). They consist in general like the pleopods of a basal segment bearing two lamellae, or raini, not being always lamelliform, and in the Tan<(Uv\\\c\ are more or less segmented (pi. XIII, fig. 8G). One of these rami may disappear, as in Sphccroma and in some of the Idoteidce (pi. V, fig. L'o c), where a further modification takes place, and the uropods are so articu- 302 REPOET OF COMMISSIONER OF FISH AND FISHERIES. latcd to the inferior surface of the pleon as to fold together like a pair of cupboard doors, forming an operculum for the protection of the more delicate pleopods. Except in the Tanaidce, respiration is carried on by means of the pleopods. In the AsellidcL', Idoteidcc, and some other families two or more of the segments of the pleon are united, so that, seen from above, the pleon, like the head, may appear to consist of a single segment, as in Jeer a albi- frons (pi. I, fig. 4), but the number of pairs of its appendages, usually six, remains as evidence of this consolidation. In like manner the head is to be regarded as composed of several segments united, and the number of such segments is indicated by the number of pairs of appen- dages. In the Tanaidce and many of the higher Crustacea, the eyes, more or less distinctly stalked or articulated with the head, are seen to be of the nature of a pair of appendages, which may be regarded as be- longing to the first cephalic segment. The antennulae and antennae represent, respectively, the second and third cephalic segments, and, in like manner, the mandibles and two pairs of maxilla3 represent the fourth, fifth, and sixth segments of the head. A seventh segment is indicated by the maxilh'peds. This segment is regarded by Huxley as properly thoracic* instead of cephalic, but, for purposes of description, the segment and its appendages will be regarded as belonging to the head, and the next segment considered the first thoracic. This segment, like the following thoracic segments, is usually free, and has the dorsal region well developed, but in the adult GnatMa it is united with the head, and still more closely so in the Tanaidce. The seventh thoracic segment is the last to develop, and in young Isopoda, taken from the incubatory pouch, only six pairs of legs are commonly found. In GnatMa this condition prevails through life, and in the adults the first pair of legs are also modified, especially in the males, so as to quite lose their pediform character, leaving apparently only five pairs of legs. Further modifications of structure will be described in the fam- ilies and genera in which they occur. The nomenclature adopted, as explained above, corresponds nearly with that proposed by Mr. C. Spence Bate in his Report on British Edriopnthalma, and used by the authors of the British Sessile-eyed Crustacea. The length of an Isopod, in the present article, is given as the length of the body, exclusive of appendages, and is measured from the front of the head to the tip of the pleon. When, as in Janira, the head is produced medially into a ''rostrum" (see pi. II, figs. 9 and 10), the meas- urement is taken from the tip of the rostrum, which is a part of the head, and not properly an "appendage." Among the Edriophthalma or sessile-eyed Crustacea, the Isopoda may in general be characterized as follows: Body depressed rather than compressed ; respiration carried on by means of the pleopods, of which the last pair only are modified into uropods. * Huxley, Anat. Inv., Am. ed., p. 276. MARINE ISOPODA OF NEW ENGLAND, ETC. 303 The body is said to be depressed, or flattened from above, in distinction from the form usually seen in the AmpMpoda, where it is in general flat- tened from side to side. An important exception to the ordinary mode of respiration occurs in the Tanaidte, as has already been mentioned. In this family respiration takes place in two lateral cavities, situated beneath the integument of a large cephalothoracic shield, covering the head and first thoracic segment. In general, as the name of the order indicates, the legs are similar in structure and function throughout, as in the " sow-bug," but may differ considerably, as in the Arcturidce, the MunnopsiddBj and the Tanaidce. The arrangement of the families in the present paper can only be re- garded as tentative, and no higher grouping will be attempted further than to indicate briefly the relationships of a few of the families to each other. The Oniscidce may, on account of their aerial respiration, be regarded as standing quite distinct from the remaining families, and should, per- haps, be further divided as proposed by Kiuahan. As they do not, how- ever, come within the proper scope of this article, I have not attempted to subdivide the family. The Bopyridce have been placed near the Onis- cidce in deference to the opinions of Dr. Fritz Miiller. Having made no study of this family myself I do not express any opinion as to the pro- priety of separating it so widely from the Cymotlioidcc, with which it has usually been associated. The Asellidce and Munnopsidce are closely allied to each other. The Idoteidce and Arcturidce form a group distinguished especially by their operculiform uropods. The above families correspond nearly with the " marcheurs" or walking Isopoda of Edwards, and more nearly with the " gehende Asseln " of Miiller. They usually have the antennulse much less developed than the antenna, and the uropods ter- minal or inferior, that is, attached to the end of the last segment, or in the last two families to its inferior surface. The Sphceromidce and Linmoriidce are closely allied, and perhaps ought hardly to be kept separate as families. The Cirolanidce, ^Egidce, and Cymothoidce form another group embracing a wide diversity of forms, from the active predatory Cirolana to the sedentary and distorted Livo- neca, and yet apparently connected by easy gradations. The remaining families are generally regarded as aberrant, and form the "Isopoda aberrantia " of Bate and Westwood. They do not present any very evi- dent relationships with the preceding. Of these the Anthuridce have usually been associated with the Idoteidce or the ArcturidcB, or with both. Except an elongated form, however, they do not appear to have much in common with either of these families. According to Dohrn's observations they are related to the Gnathiidce in the structure of the incubatory pouch. The Gnathiidce have the head united with the first thoracic segment, as in the Tanaidce, but this last family is widely sep- arated from the others, and doubtless ought to be regarded as forming a distinct suborder, according to the views of Dr. Fritz Miiller. 304 REPORT OF COMMISSIONER OF FISH AND FISHERIES. The arrangement of the families adopted, and to a certain extent their affinities, are indicated in the subjoined table, in which, however, a,s throughout the article, special reference is had to the representatives of the order in New England waters, extralimital species, genera, and even higher groups, Apscudes and the Serolids, for example, being disre- garded. The arrangement will be seen to considerably resemble that of Dr. Fritz Miiller. I have placed the Tanaidce at the other end of the order, partly, however, from the necessity of a lineal arrangement. SYNOPTICAL, TABLE OF FAMILIES. I. Respiration pleonal ; legs not furnished with a clielate hand. 1. Legs in seven pairs. a AntennulfB small or rudimentary ; antennae longer, often much elongated, t Uropods terminal, sometimes rudimentary, rami mostly styliform. Legs ambulatory ; antennulas rudimentary ; respiration aerial. I. OXISCIDJE, p. 305 Legs prehensile ; sexes very unlike ; adult forms degenerate ; para- sitic II. BopYnrrxE, p. 311 Legs ambulatory or prehensile; segments of pleon united ; antennae with a multiarticulate flagellum III. ASELLHXE, p. 312 Last three pairs of legs natatory; segments of pleon united; antennas with a multiarticulate flagellum IV. MUNNOPSID^E, p. 328 tt Uropods inferior, operculiform. Legs prehensile or ambulatory, not ciliated V. IDOTEIIXE, p. 335 First four pairs of legs ciliated ; last three pairs ambulatory. VI. ARCTURID^E, p. 361 6 Antennulae and antennae subequal ; body not elongated. t Uropods lateral, with one ramus obsolete or subrudimentary. Anteunulae and antennae well developed ; pleon of two segments ; uropods with one movable ramus VII. SPH^EROMID^E, p. 367 Antennulas and antennas short ; pleon of six segments ; outer ramus of nro- pods small VIII. LIMNORIID^E, p. 371 tt Uropods lateral, distinctly biramous; rami mostly lauielliform. Mouth caruassial ; legs not ancoral ; autennuloe exposed in front ; pleopods ciliated IX. CIROLANHXE, p. 376 Mouth suctorial ; first three pairs of legs ancoral ; antennulaa exposed in front X. JEGiDJE, p. 382 Mouth suctorial ; legs all ancoral ; antennnlas concealed at base by the pro- jecting front ; pleopods naked XL CYMOTHOHXE, p. 390 cAntenuuLe and antennas subequal, or antennulas much the largest in the males; body cylindrical, elongated, t Uropods lateral and superior. Legs ambulatory or prehensile XII. ANTHURID^E, p. 396 2. Legs in the adult in six, apparently only five, pairs. Five pairs of legs ambulatory ; anteunulas and antennas subequal. XIII. GXATHIIDJE, p. 408 II. Respiration cephalothoracic ; first pair of legs terminated by a chelate hand. Legs ambulatory and prehensile ; head united with the first thoracic seg- ment ; antenuular flagellum single XIV. TANAID^E, p. 413 MARINE ISOPODA OF NEW ENGLAND, ETC. 305 I. ONISCHXE. Antennulae rudimentary ; legs ambulatory ; pleon of six distinct aeg- ments, of which the last is small ; mandibles without palpi ; uropods terminal.* This large and important group of Isopoda being terrestrial in habit, only a few species are mentioned in this paper. They inhabit moist situa- tions, and are commonly known as "sow-bugs," "pill-bugs," "wood-lice," &c. Several species may often be found under an old board or pile of rubbish. The genus Ligia Fabr. inhabits sea-shores, above tide-level, and a few other genera are found under heaps of seaweed, or burrowing in the sand along the shore. Three such species, belonging to as many genera, are here described and figured, but are less fully treated of than the marine species that follow in the other families. Other species, especially of the genus Porcellio, may be found in similar situations. The family may be at once recognized by the apparent possession of only a single pair of antennae. These are the antennae properly so called, the antennulae being minute and rudimentary. This is generally regarded as a character indicating a high degree of development, and causes them to somewhat resemble externally some of the shorter myrio- poda, which, like other insects, have but a single pair of antennary organs. The maxillipeds are large and operculiforni in this family, with short and few-jointed palpi. The mandibles are destitute of palpi. The legs are rather weak and fitted only for walking, and usually more or less concealed by the projecting epimeral regions of the thoracic seg- ments. The pleon, in our species, has its segments distinct and decreas- ing rapidly in size to the last, which bears the more or less exserted uro- pods. These organs may not, however, project beyond the general outline of the pleon, as they scarcely do in Actoniscus, while in Armadillo they assist in forming the very regular outline of that part of the body, which closes against the head when those animals, as is their habit, roll themselves into a ball on being alarmed. This family is placed by Bate and Westwood in a separate "division," the "2Ero-spirantia," on account of their aerial respiration. The air, however, requires to be saturated with moisture, and in some of the genera the respiration is, in part at least, aquatic. On this subject the reader is referred to the publications of Duvernoy and Lereboullet and of Nicholas Wagner. > Philoscia Latreille. PMIoscia Latreille, Hist. nat. des Crust, et des Ins., tome vii, p. 43, '''1804." Head rounded in front, not lobed j antennas with its segments cylin- drical, flagellmn three-jointed ; pleon suddenly narrower than the thorax; uropods exserted, basal segment broad, rami elongate. * The above diagnosis would not include the genera Ti/lus Latreille nor Helleria Ebner, which perhaps ought not to be regarded as belonging to this family, although closely allied to it. 20 F 306 REPORT OP COMMISSIONER OF FISH AND FISHERIES. This genus may be recognized among our Onlscidce by the rounded head without lobes, and the conspicuously narrowed pleon. Only a single species is as yet known from New England. PMloscia vittata Say. Philosda vittata Say, Jour. Acad. Nat. Sci., vol. i, p. 429, 1818. Dekay, Zool. New York, Crust., p. 50, 1844. White, List Crust. Brit. Mus., p. 99, 1847. Harger, This Report, part i, p. 569 (275), 1874 ; Proc. U. S. Nat. Mus., 1879, vol. ii, p. 157, 1879. PLATE I, FIG. 1. This species may be recognized, among our terrestrial Isopoda, by the absence of the usual autero-lateral processes on the head, in front of the eyes, and by the sudden contraction of the body at the base of the abdomen or pleon. Body oval, smooth; about twice as long as broad; head nearly twice as broad as long; eyes large, occupying the antero-lateral regions of the head. The antenuulae are minute and concealed from above. An- tennae minutely hirsute, especially on the last three, or flagellar, seg- ments, inserted below the inner margin of the eyes ; first segment short ; second about twice as long as the first ; third equal in length to the sec- ond, clavate; fourth longer cylindrical; fifth longest, slender, cylindrical, straight; flagelluin slender, three-jointed, longer than the fifth or last peduncular segment; first flagellar segment about one-half longer than the second ; third longer than the second, tapering, tipped with a short transparent filament. The first thoracic segment is longer than the following ones, which are of about equal length. The anterior angles of the first thoracic segment are somewhat produced at the sides around the head ; the posterior angles are broadly rounded. The second and third segments have their pos- terior angles less broadly rounded, but not at all produced backward. In the fourth segment this angle is scarcely produced, but in the fifth, and still more in the sixth and seventh, it becomes produced and acute. The legs increase in size and length from the first to the seventh pair, and are well armed with spines, especially upon the inferior surfaces of the meral, carpal, and propodal segments. The spines on the latter seg- ment are, however, much smaller than those on the merus and carpus. The pleon is at the base about two-thirds as wide as the seventh thoracic segment. In the first two segments of the pleon the coxae, or lateral lamel- lae, are short, small, and nearly concealed by the seventh thoracic segment, but in the third, fourth, and fifth segments they are evident and acute but not large. The sixth segment is acute but not prolonged behind, and ex- tends beyond the end of the basal segment of the uropod, which is broad and bears the two rami nearly on the same transverse line. The outer ra- mus, seen from above, is narrowly and obliquely lanceolate in outline, tapering to the tip, and surpasses by less than half its length the more slender, styliform inner rainus. The uropods, the legs and antennae, and the segments of the pleon, along their margin, are very minutely hirsute. MARINE ISOPODA OF NEW ENGLAND, ETC. 307 The color of these animals is dull and somewhat variable, usually brownish or fuscous, with lighter margins and two broad dorsal vittse. Length 8 mm , breadth 4 mm . This species has been found under rubbish and stones from Great Egg Harbor, ! K J., to Barnstable, ! Mass. All the specimens that I have seen have been from the coast, although Say states that it is " very common under stones, wood, &c., in moist situations." , Specimens examined. Number. Locality. Habitat. When col- lected. Received from Number of specimens. Dry. Ale. 1222 Somers and Eeesley's Points Shore . . .... - 1871 A. E. Verrill and Ale* N. J. S. I. Smith 25 1911 Stony Creek, Conn . ... do .. A. E. Verrill Ale. 2146 Vineyard Sound, Mass ...do , 1871 U. S. Fish Com . . . 8 Ale. 1910 Barnstable, Mass ...do Aug. 30, 1875 do 3 Ale. Scyphacella Smith. Scyphacella, Smith, This Report, part i, p. 567 (273), 1874. Antenna composed of eight distinct segments, with a geniculation at the articulation of the fourth with the fifth segment ; terminal portion, or ftagelluni, composed of three closely articulated segments besides a minute apical one; mandibles slender; exposed portion of the inaxilli- peds formed of only two segments. The genus Scyphacella was founded by Professor S. I. Smith, in j>art I of this Report, for the reception of the following species, the only one yet known. In regard to the relations of the present genus with Scypliax Dana* Professor Smith says : " This genus differs from Scypliax most notably in the form of the inaxillipeds, which in Scypkax have the ter- minal segment broad and serrately lobed, while in our genus it is elon- gated, tapering, and has entire margins. In Scypliax, also, the posterior pair of thoracic legs are much smaller than the others, and weak ; the last segment of the abdomen is truncated at the apex, and the articula- tions between the segments of the terminal portion of the antenna, are much more complete than in our species. The general form and appear- ance of the genera are the same, and the known species agree remark- ably in habits, the Scypliax, according to Dana, occurring on the beach of Parua Harbor, New Zealand, and found in the sand by turning it over for the depth of a few inches." Scyphacella arenicola Smith. Scyphacella arenicola Smith, This Report, part i, p. 568 (274), 1874. VerriU, This Report, part i, p. 337 (43), 1874. Harger, Proc. U. S. Nat. Mus., 1879, vol. ii, p. 157, 1879. PLATE I, FIG. 2. The small size, nearly white color, and peculiarly roughened surface of this Isopod will in general serve for its recognition, and the presence * U. S. Exploring Expedition, Crustacea, p. 733, pi. 48, fig. 5. 308 REPORT OF COMMISSIONER OF FISH AND FISHERIES. of eyes will further distinguish it from Platyarthrus, which is often found inhabiting ants' nests, but would hardly be likely to occur in the sand of the beach. Body elliptical, pleon not abruptly narrower than the thorax, dorsal surface roughened throughout with small depressed tubercles each giving rise to a minute spiuule. Head transverse, not lobed ; eyes prominent, round 5 antennae longer than the breadth of the body ; with the first and second segments short ; third, fourth, and fifth successively longer and of less diameter ; flagellum shorter than the fifth segment, composed of three closely articulated, successively smaller segments, and a very short somewhat spiniform but obtuse terminal one ; all the segments, except the minute terminal one, beset with small scattered spinules. First thoracic segment scarcely embracing the head at the sides ; sec- ond, third, and fourth segments each about as long as the first, but in- creasing in breadth ; fifth, sixth, and seventh diminishing in length and the last two also in breadth. Posterior lateral angles of the first three segments not at all produced, hardly perceptibly produced in the fourth segment; fifth, sixth, and seventh with the angles increasingly produced but not acute. Legs increasing somewhat in size posteriorly, armed, especially on the inferior surface of the nieral, carpal, and propodal seg- ments, with short stout spines. Segments of the pleon with the coxos but little developed. Ter- minal segment slightly rounded at the end, not attaining the end of the basal segment of the uropods, which are robust, with the basal segment spiuulose, tapering to the base of the short, stout, outer ramus, and bearing the more slender inner ramus much nearer its base. The inner ramus is actually longer than the outer, but being inserted much lower down does not attain the tip of the outer ramus ; both are tipped with setae. " Color, in life, nearly white, with chalky white spots, and scattered, blackish dots arranged irregularly. Eyes black." Length 3.4 mm . This species was " found at Somers and Beesley's Points, on Great Egg Harbor ! , New Jersey, in April, 1871, burrowing in the sand of the beaches, just above ordinary high- water mark, in company with sev- eral species of Staphylinidce," and has also since been found by Pro- fessor Smith at Nobska Beach, Vineyard Sound ! , Mass., in 1871, and by Mr. Y. 1ST. Edwards, on the beach at Nantucket Island ! , December 6, 1877. It will doubtless be found at other points along the coast and toward the south. Specimens examined. "o tn a (H O Locality. Habitat. When col- lected. Received from !! Dry. Ale. fe (3 10 Great E. 11, 1804. Body contractile into ;i, sphere; antemmhe and antenna', short or of moderate length; maxillipeds with a live jointed palpus; legs all ambu- liilory; daclyli short and thick ; nropods short, rainns and basal seg- ment siibeqiial. The, name of this genus is derived IVom the peculiar habit, of many Of the Species Of rolling themselves into a, ball when alarmed. The, body is so constructed as l,o I'aeililate tin's operation, the antennnhc and antenna) being received into a groove at the, side of the. head; the cpi- meral regions of the, thoracic segments behind the first are, narrowed nearly to a point and project well downward so as to moot very close together and still leave room for the included legs, while t lie nropods, shutting together like a pair of scissors, ibid also partly under the largo terminal segment of the, pleon and till the crevice between tin- pleon and the head. The maxillipeds in this genus are provided with a long densely ciliated live-jointed palpus. The, maxill;u are much as in the Idotcidcc, the outer pair three-lobed and strongly ciliated, the inner two lobed with the inner lobe small and tipped with pectinate seta 1 , the outer larger and armed with curved denticulated spines. The mandibles have, a strong molar process, a dentigerous lamella armed with acute teeth, and a throe-jointed palpus. The, legs are rather weak and nearly alike throughout, all ambulatory. The, pleon is scarcely narrower than the segments of the thorax and ap- pears to consist of two* segments only, of which the first is much like the last thoracic segment, but more strongly produced at the sides than is that segpient and marked with impressed lines. It is articulated with considerable motion to the large scutiform terminal segment, which, in this genus, is rounded and entire at the lip, and not strongly tubercu- lated nor spiny. Anteriorly, the angles of this segment are, produced downward into a rounded lobe in front of the shoulder from which arise the nropods. These organs are not greatly elongated ; the basal seg- ment is produced into a plate about equal in si/e to the single ramus. Sphaeroma quadridentatum Say. flphatroma qiindridcnlnla Say, Jour. Acad. Nat. Sci. Phil., vol. i, p. 400, 1818. Dokay, Zool. Now York, Crust., p. -14, 1HM. Whito, Lint Criwfc. Brit. Mus., p. HfcJ, fH47. Harder, Am. .lour. Sci. ,111, v., p. :'.! 1, |H~:5; This Report, parti, p. 569 (275), pi. v., fig. 21, 1874; Proc. U. S. Nat. Museum, 1879, vol. ii, p. 161, 1879. Von-ill, This Report, part, i, p. :Uf> ('21), 1H74. PLATH IX, FIG. 53. The outline of the body when extended is a pretty regular ellipse, but the animal, when disturbed, rolls itself into a ball with facility, and by *Tlio pleon is iiuulverUmUy iloscrilxnl l>\ l!:i,l,o :m), the last two being together about equal in length to the first three, instead of far surpassing them as in the Asellidce ; the flagel- lurn is short and few-jointed, mostly made up of a tapering basal seg- ment, and not at all resembling the slender ruultiarticulate flagellum of the Asellidce. The mandibles are adoptively modified in accordance with the boring habits of the species, but the other mouth parts do not seem to present characters from which comparisons need be drawn with other families. The legs are somewhat similar to those seen in many Asellidce, being furnished with short dactyli, each armed with a strong curved claw, and a shorter spine below. A similar form of leg is, however, seen in SpTice- roma. The epirnera are united to the lateral margins of the thoracic segments almost precisely as in Spliceroma, an arrangement that does not prevail in the Asellidce. The pleon has all its six segments well developed and perfectly separated from each other, while in the Asellidce they are united into a single scuti- form segment, or at most, the basal segment only is more or less distinct. The pleopods are of the normal number and similar in form and texture throughout ; the anterior pairs are ciliated. Each pair of pleopods consists of a basal segment, bearing an inner narrow lamella and an outer oval one, which, except in the fifth pair, are well ciliated. In the male the inner la- mella of the second pair bears, on its inner margin, a stylet, as in Sphceroma and many other genera of Isopoda. In the Asellidce the branchial pleo- pods are in fewer than five pairs, and are protected in front by a simple or compound operculum of firmer texture than the other pleopods. Dr. Coldstream * fell into an error in describing the respiratory organs as con- sisting of " six pairs of scale-like bodies, pendant from the anterior seg- ments of the tail, * * arranged in three rows, in an imbricated man- ner, one of each kind ('oval' and 'nearly quadrangular') being articu- lated together on a common peduncle on either side." He further describes, loc. cit., p. 324, " two vesicular bodies of an oval form" behind the branchiae. These organs were without doubt the external lamellae of the fifth pair of pleopods, as shown by his figure. There are, how- ever, four instead of three ciliated pairs anterior to the last pair, one of which was overlooked by Dr. Coldstream, and in this error he has been followed by Bate and Westwood. t If the observations of Dr. Cold- stream had been correct, an affinity might have been indicated with the Asellidce. The terminal segment is flattened and scutiform, in shape resembling that of Jccra, but the uropods are strictly lateral, being attached at the broadest part of the segment and in front of the middle. * Edinburgh New Phil. Journal, vol. xvi, p. 323. t Brit. Sessile-Eyed Crustacea, vol. ii, p. 350. MARINE ISOPODA OF NEW ENGLAND, ETC. 373 The relations of the present family with the Sphceromidce appear to be more close, but the structure of the mandibles and perhaps also that of the inaxillipeds, the fully segmented pleon and the biramous uropods seem to be characters of family value, which, however, a fuller investi- gation of the boring Spliccromidce might go far to break down. Limnoria Leach. Limnoria Leach, Edinburgh Encyc.,-vol. vii, p. "433" (Am. ed., p. 273), "1813-14." Mandibles with a nearly even chisel-like cutting-edge at the tip and no molar process; inaxillipeds elongate, with a well developed external lamella and a five-jointed palpus; first thoracic segment large; uropods with the outer rarnus very short and almost obsolete. The above characters differ from those by which Leach separated this genus from Cymothoa and the Sphccromidce, with which he associated it. Linmoria lignorum White (Eathke). "Cymothoa lignorum Eathke, Skrivt. af Naturh. Selsk., v. 101, t. 3, f. 14, 1799" (White). Limnoria lerebrans Leach, Ed. Encyc., vol. vii, p. '433' (Am. ed., p. 273), "1813-14"; Trans. Linn. Soc., vol. xi, p. 371, 1815; Diet. Sci. nat., tome xii, p. 353, 1818. Samouelle, Ent.. Cornp., p. 109, 1819. Desmarest, Cousid. Crust., p. 312, 1825. Latreille, Regne Anim., tome iv, p. 135, 1829. Coldstream, Ediiib. New Phil. Jour., vol. xvi, pp. 316-334, pi. vi, 1834. "Hope, Trans. Ent. Soc. Loud., vol. i, p. 119" (B. & W.). Thompson, Edinb. New Phil. Jour., vol. xviii, p. 127, 1835; Ann. Mag. Nat. Hist., vol. xx, p. 157, 1847. Templeton, Loud. Mag. Nat. Hist., vol. ix, p. 12, 1836. Moore, Charlesworth's Mag. Nat. Hist., n. s., vol. ii, p. 206, 1838; ibid., vol. iii, pp. 196, 293, 1839. Edwards, Aunot de Lamarck, torn, v, p. 276, 1838; Hist. nat. des Crust., torn, iii, p. 145, 1840; Regne Anim. Crust., p. 197, pi. 67, f. 5, 1849. Gould, Invert. Mass., pp. 338, 354, figure, 1840. Flemiug, Eucyc. Brit., 7 ed., vol. vii, p. 502, 1842. Dekay, Zool. New York, Crust., p. 48, pi. ix, fig. 33, 1844. "Kirby and Spence, Int. Entom., 5th ed., p. 238; 6th ed., p. 203" (White.) White, List Crust. Brit. Mus., p. 96, 1847; Brit. Crust. B. Mus., p. 68, 1850. Dalyell, Powers of the Creator, vol. i, p. 241, pi. Ixv, figs. 7-15, 1851. Leidy, Jour. Acad. Nat. Sci. Phil., II, vol. iii, p. 150, 1855. Gosse, Man. Mar. Zool., vol. i, p. 136, fig. 242, 1855. Steenstrup and Liitken, Vidensk. Meddel., II, vol. ii, p. 275, 1861. Hesse, Ann. Sci. nat., Zool., V, tome x, p. 113, 1868. Jones, Trans. Nova Scotian Inst. Nat. Sci., vol. ii, pt. iv, p. 99, 1870. Verrill, Proc. Am. Assoc., 1873, p. 367, 1874. Macdonald, Trans. Linn. Soc., II, Zool., vol. i, p. 67, 1875. Andrews, Q. Jour. Mic. Sci., II, vol. xv, p. 332, 1875. Limnoria lignorum White, Pop. Hist. Brit. Crust., p. 227, pi. 12, fig. 5, 1857. Bate, Rep. Brit. Assoc., 1860, p. 225, 1861. Bate and Westwood, Brit. Sess. Crust., vol. ii, p. 351, figure, 1868. 374 REPORT OF COMMISSIONER OF FISH AND FISHERIES. Limnoria lignorum Continued. Norman, Rep. Brit. Assoc.,1868, p. 288, 1869. Mobius, Wirbcllos. Thiere cler Ostsee, p. 122, 1873. Parfitt, Fauna of Devon, Sess. Crust., p. (19), 1873. Verrill, Ain. Jour. Sci., Ill, vol. vii, pp. 133, 135, 1874; Proc. Am. Assoc., 1873, p. 371, 1874 ; This Report, part i, p. 379 (85), 1874. Harger, This Report, part i, p. 571 (277), pi. vi, fig. 25, 1874 ; Proc. U. S. Nat. Mus., 1879, vol. ii, p. 161, 1879. M'Intosh, Ann. Mag. Nat. Hist., IV, vol. xiv, p. 273, 1874. Stobbiug, Trans. Devon. Assoc., 1874, p. (8), 1874. Ann. Mag. Nat. Hist., IV, vol. xvii, p. 79, 1876. Whiteaves, Further Deep-Sea Dredging, Gulf St. Lawrence, p. 15, " 1874." Metzger, Nordseefahrt der Pomm.,p. 285, 1875. Meiuert, Crust. Isop. Amph. Dec. Daniae, p. 77, 1877. Smith, Proc. U. S. Nat. Mus., 1879, vol. ii, p. 232, fig. 2, 1880. Limnoria uncinata Heller, Verh. k. k. Zool. bot. OJes. Wien, B. xvi, p. 734, 1866. Stalio, Cat. Crost. Adriatic, p. 211, 1877. PLATE IX, FIGS. 55-57. This species may in general be recognized by its habits, being usually found burrowing in submerged timber, to which, notwithstanding its insignificant appearance, it often proves very destructive. The body is subcyliudrical, tapering slightly at each end and covered above with short hairs to which more or less dirt usually adheres. The head is narrower than the first thoracic segment. The eyes are lateral and consist of about eight ocelli, one central and the others around it. The antenuulae (pi. IX, fig. 56 a) are short and seem to arise from near the middle of the front of the head. The basal segment is the largest ; the sec- ond and third are of slightly decreasing size ; the fourth or flagellar seg- ment is much the smallest, and tipped with setae. The antennae (pi. IX, fig. 56 &) are more slender than the anteunulae, and arise just below their bases and a little farther apart. The first two segments are short; the third slightly longer; the fourth and fifth increasing somewhat in length; the flagellum is not longer than the last two peduncular segments, and consists of a tapering segment, followed by a few short terminal seg- ments provided with a terminal brush of setae. The inaxillipeds (pi. IX, fig. 56 c) are slender; the external lamella is semi-ovate, with the inner margin nearly straight, acute, and ciliated ,t the tip ; the palpus is five-jointed but short, with the segments flattened, and all but the first ciliated along their inner margins. The outer maxilla (pi. IX, fig. 56 d) a,re slender, three-lobed, and ciliated at the tip. The inner maxillae (pi. IX, fig. 56 e) are also slender, the inner lobe tipped with pectinate bristles, the outer with robust spines. The mandibles (pi. IX, fig. 56/j are some- what elongate, but of a simple form, being curved inward, flattened and chisel-shaped at the tip ; below there is a slight tubercle, apparently the rudiment of the molar process ; externally, above the origin of the palpus, is a prominent tubercle ; the palpus is short, of three subequal segments, the last furnished with a rather imperfect comb of setae. The first thoracic segment is about twice as long as any that follow; it is crossed by a broad, shallow depression, and is rounded at the sides. MARINE ISOPODA OF NEW ENGLAND, ETC. 375 The second and third segments are each about half the length of the first. The epimeral sutures are evident, and the epimera are rounded behind in the second segment, but a little more prominent in the third, becoming acute and increasing in size and extension backward to the seventh. The fourth segment is slightly shorter than the third, and per. haps a little broader; the last three are short, decreasing in length to the seventh, but maintaining about equal width. The legs are short and rather robust. The first pair have the carpus triangular, but this seg- ment becomes more elongate in the succeeding pairs. The dactyli are robust, and are armed with a strong curved spine or claw at the tip and a smaller one below it. The merus, and usually the ischium and carpus, bear a few spiuiform tubercles on the lower surface except in the last pair, which are also more elongated and slender than the others. The pleon is scarcely narrower than the thorax, and tapers but little ; the first four segments are of equal length 5 the fifth is longer with a median elevation and a transverse depression on each side. The last segment (pi. IX, fig. 57 a) is transversely oval or subcircular, broader than long, with the anterior margin raised, especially at the middle, where the elevation is continued a short distance on the segment, but posteriorly it is flattened. The posterior margin is ciliate with hairs of various lengths. The uropods (pi. IX, fig. 576) are attached just in front of the middle of the segment at its widest part. They consist on each side of a somewhat wedge-shaped basal segment, ciliated and bluntly denticu- lated distally on the outer side, and supporting two rami, between which it is produced below into a strong tooth-like process. The outer ramus is very short and curved outward ; the inner is not as long as the basal seg- ment, and is ciliated externally and at the tip. Underneath, the pleoii is much excavated for the pleopods, which are strongly ciliated. The first pair (pi. IX, fig. 57c) consist on each side of a short basal segment bear- ing two lamella; the inner lamella is almost four times as long as broad, with nearly parallel sides, ciliated at and near the tip ; the outer, which is also in front of the inner, is sub-oval with the outer margin more convex than the inner, ciliated near the tip and along most of the outer margin, and inserted a little obliquely upon the basal segment. The next three pairs of pleopods are similar to the first pair on each side, except that in the males the second pair (pi. IX, fig. 57 d) bears a stylet (s) articulated to the inner margin of the inner lamella about the middle, The posterior pair of pleopods are smaller than the others and not ciliated. Length 4.5 mm ; breadth 1.5 mm ; color light grayish. Much has been written upon the destructive habits of the Limnoria or "gribble" and the means of preventing its attacks on woodwork, for which the reader may consult especially the publications of Leach, Cold- stream, Hope, Thompson, Moore, Gould, Bate and Westwood, Verrill, and Andrews, who has observed it attacking the gutta-percha of submarine telegraph cables. 376 REPORT OF COMMISSIONER OF FISH AND FISHERIES. It is found boring in submerged wood along our coast from Florida! to Halifax!, 1ST. S., and the Gulf of St. Lawrence. It occurs above low- water mark, but does not usually live far below that line; it has, however, been found by Professor Verrill at a depth of 10 fathoms in Casco Bay, and was dredged by the II. S. Fish Commission in a depth of 7|- fathoms, Cape Cod Bay!, Mass., in the summer of 1879. It is abundant, according to European authors, in many localities on the coast of Great Britain and in the North Sea. L. uncinata Heller, from Verbosca, in the Island of Lesiua, Adriatic Sea, appears to be the same species, as the differences pointed out by Heller do not really exist, but were doubtless suggested by the incorrect figures that have been published representing' the uro- pods with rami composed of two or more segments. The form of these appendages, as shown on plate IX, fig. 57 &, corresponds well with Hel ler's description. It was found by Heller associated with Clielura tere- brans. Limnoria is said also to occur in the Pacific Ocean, and from its habits might be expected to have a wide distribution. Specimens examined. Number. Locality. Habitat. When col- lected. Received from Number of Specimens. Dry. Ale. 2048 Florida Boring in wood Smithsonian Inst 6 Ale Provincetown Mass . do Aug. 1879 TJ. S. fish Com 00 Ale 2047 Oasco Bay ... do 1873 do 30 Ale. Bay of Fundy do , 1872 do 00 Ale. Halifax, N. S ....do , 1877 .do 00 Ale. IX. CIEOLANID^B. Front formed of the approximate basal segments of the antennuloe, which are not covered by an anterior projection of the head ; antennuhe and antennae presenting an evident distinction into peduncular and flagellar segments; maxillipeds with a five-jointed palpus; mandibles formed for biting, palpigerous; legs all terminated by nearly straight dactyli ; epimera distinct behind the first thoracic segment ; pleopods at least the anterior pairs, ciliated; uropods biramous, the rami flattened and ciliated. This family is represented on our coast by two closely allied species apparently belonging to the typical genus Cirolana, although approach- ing the allied genus Conilera, to which I formerly referred them. They have been hitherto usually referred to the following family, but the dif- ferences in the structure of the mouth parts, first pointed out by Schiodte, seem to warrant their separation as a distinct family. The mandibles are formed for biting, being armed with long and powerful teeth, which, closing together like the blades of scissors, are well adapted for lacerat- ing the flesh of fishes on which they feed. The first three pairs of legs are fitted for prehension, but they are destitute of the strongly curved MAEINE ISOPODA OF NEW ENGLAND, ETC. 377 * dactyli found in the JEgidcc, and still better developed in the Cymothoidce. In the Cirolanidw the propodus, in the first three pairs of legs, is some- what curved and the dactyli are nearly straight, so that while the first three pairs of legs are powerful organs of prehension, they are also capable of letting go preparatory to the seizure of another victim. The posterior pairs of legs are ambulatory or fitted for swimming by their form and armature of bristly hairs. The ciliated pleopods are also powerful swimming organs, so that these animals are well fitted for the predatory life they lead. The epimera are well separated by sutures in all the thoracic segments behind the first. The pleon is scarcely nar- rower at base than the last thoracic segment, and is composed of six distinct segments, of which the last is much the longest, but not broader than the preceding segments, and tapers posteriorly. The uropods arc lateral, articulated near the base of the last segment and distinctly biramous. The mouth-organs of this and the two following families have been the object of special research by J. C. Schiodte, whose papers in the Natur- historisk Tidsskrift have been in part translated in the Annals and Magazine of Natural History. He regards Girolana as representing " the highest development of the crustacean type among the Isopoda," and even hints that Cirolana and JEga should be removed to opposite ends of the series of Isopoda. The same author would closely unite the Bopy- ridcc, JEya, and the Cymothoidce into a single group, the Cymothoce, while acknowledging that the young of Cymotlioa oestrum, " according to the classification hitherto current, * * * would rather be allied to Cirolana than to Cymothoa." His classification, however, appears to be based almost entirely upon the structure of the mouth, disregard- ing the totality of structure upon which alone morphological classi- fication can securely rest. In deference, however, to his views I have here regarded Cirolana as the type of a distinct family, which must still be considered as closely related with the two following families, on the principle that it is " more important that similarities should not be neg- lected than that differences should be overlooked." Among the more important of the similarities by which these fami- lies seem to be united may be mentioned the following, as exemplified by our species. The segments of the thorax and pleon are all distinct from each other, so that the body, in the adults, appears to consist of thirteen segments behind the head, although in the genus OurozeuTctes Edwards* the segments of the pleon are consolidated. The epimera are distinct in all the segments behind the first thoracic. The pleon may or may not taper from the base, but it is terminated by a large scutiform segment, sometimes more or less sculptured, and bearing at the sides, near the base, a pair of uropods, in which the basal segment is more or less oblique distally and the rami lainelliforrn, though one of them may be narrowly so. The pleopods are unprotected by any form * Hist. nat. des Crust., tome iii, p. 275, 1840. 378 REPORT OF COMMISSIONER OF FISH AND FISHERIES. of operculum and the anterior pairs are ciliated in the young of all three families, but this ciliation, as well as that on the uropods, may be lost in the sedentary adults of the Cymothoidcv. In all our species the dorsal surface is smooth throughout, or minutely punctate under a lens, but destitute of distinct roughness, tuberculation or sculpture, except that the telson may be faintly grooved or sculptured, and in some foreign species more distinctly so. Cirolana Leacli. Cirolana Leach, Diet, des Sci. nat., tome xii, p. 347, 1818. Thoracic segments subequal; eyes small, well separated; mandibles armed with strong acute teeth ; dactyli straight, or but slightly curved ; pleon of six distinct segments ; basal segment of uropods with the inner angle produced. Two closely allied species are found on this coast, which I formerly referred to the genus Conilera Leach. Further consideration induces me to refer them rather to the present genus, although they have some features which point toward Conilera, and are perhaps between that genus and the typical forms of Cirolana. From Conilera, as described by Bate and Westwood, our species differ principally in the more robust four posterior pairs of legs, in the produced angle of the basal segment of the uropods, and in the structure of the first pair of pleopods, which are not operculiform either in size or texture. Of these two species one is abundant and is described at length. The description will, however, apply almost equally well to the other except in the few points mentioned in the appropriate place. The characters given, though slight, appear to be constant, and I have therefore retained the two specific names. This genus differs from JEV/ in the structure of the legs, and was placed by Professor Dana in a separate subfamily. In Cirolana the first three pairs of legs are strong, and armed with minute spine-like claws at the tip of the nearly straight dactyli ; the propodi in these legs are robust, spiny, and somewhat curved, and some of the preceding segments are also armed with spines. These legs thus form powerful organs for seiz- ing living prey, and are not, as in the Cymothoidw, and, in a less degree, in JEga, merely fitted by their curved dactyli to retain the hold of the animal upon its host in a parasitic existence. The last four pairs of legs are well ciliated and capable of use either for walking or swim- ming, and these animals are thus fitted for their active and predaceous life. Cirolana concharum Harger (Stirnpson). JEga concharum Stimpson, Mar. Inv. G. Manan, p. 42, 1853. Liitken, Vidensk. Meddel. , 1859, p. 77, 1860. Conilera concharum Harger, This Report, part i, p. 572 (278), 1874. Verrill, This Report, part i, p. 459 (165), 1874. Cirolana concharum Harger, Proc. U. S. Nat. Mus., 1879, vol. ii, p. 161, 1879. MARINE ISOPODA OF NEW ENGLAND, ETC. 379 PLATES IX AND X, FIGS. 58-63. This species may be most readily recognized among our Isopoda by the distinct thoracic and abdominal segments, the small lateral eyes, and the evident distinction, in both autennula3 and antennae, of pedun- cle and flagelluni. From the next species it is distinguished by the tip of the telson, which is truncated, or slighty emarginate, and grooved on the median line above near the end. The body is, when extended, about three times as long as broad, and is smooth and polished throughout. The head is quadrate, a little broader in front than behind, and embraced at the sides by the first thoracic segment. The eyes are triangular, with the angles rounded, and are often partially covered below by the projecting anterior lobes of the first thoracic segment. They are separated by about three times their long- est diameter. The antennuh^ (pi. X, fig. 60) are robust, with their basal segments in contact; the first segment is short and sub-spherical; the second also short ; the third cylindrical and as long as the first two taken together and followed by a robust, but short, tapering flagellum, consisting of about fifteen segments, of which the second is as long as any other two, but the rest are all short. The flagellar segments beyond the first are provided each with a tuft of " olfactory setae." The antennae (pi. X, fig. 61 ) are longer and more slender than the antennula3, and are separated at their bases. The first four peduncular segments are robust ; the first two short ; the third and fourth each about twice as long as the first or second, and the fifth or last peduncular segment slightly the longest and much the most slender. The fourth and fifth segments bear along the distal portion of their outer margins long bristle-form hairs. The flagellum is slender and composed of from li> to 18 segments, each bearing a few short bristles. The maxillipeds (pi. X, fig. 62 ) are elongated and almost pediforin but flattened ; the external lamella is small and subtriangular, rounded and hairy at the tip ; the palpus is five-jointed, with the last four segments broad, flattened, and well ciliated ; the tip of the maxilliped, nearly concealed by the large palpus, is provided with very densely plumose bristles. The outer maxillaB (pi. X, fig. 61 b) are short and robust ; the two articu- lated lobes narrow ovate, rounded at the tip, armed, especially the inner one, with spines and plumose or pectinated bristles. The inner maxillte (pi. X, fig. 61 c) are robust, with the outer lobe armed with strong smooth spines ; the inner lobe rounded at the end and bearing three straight rather blunt spines, densely covered toward the tip with soft hairs. The mandibles (pi. X, figs. 61 d) are robust and horny at the tip, armed with one strong acute tooth, and in the right mandible with one acute and one obtuse tooth along a cutting edge, while the left mandible has three less acute teeth along this edge. Each mandible is, moreover, provided with a molar process or area (w), on its inner surface set along its interior and upper margin with spines. A narrowly lanceolate leaf- like appendage is attached just below the molar area. This appendage 380 REPORT OF COMMISSIONER OF FISH AND FISHERIES. is furnished with a few bristles near the base, and its upper edge is armed with minute denticles; it is movable and ordinarily concealed behind the mandible. On the external surface, just above the origin of the palpus, each mandible bears two elevated, conical, obtuse tuber- cles. The palpi are slender, the second segment longest and hairy on the margin beyond the middle, the last segment slender and curved, with the usual hairs or slender bristles along the inner curvature. The second and third thoracic segments are a little shorter than the others, which are of about equal length. The fourth and fifth segments are widest. The first segment is produced at the sides around the head so as to very nearly attain the anterior lateral angles of the head, and joften so as to obscure the lower margin of the eyes. The epiineral su- tures are scarcely distinguishable in this segment, but evident in the following segments. The epimera are rounded behind as far as thA m* 1 NKW KNUI.ANM, RTG 885 li.i\ Ihcn In I !< in. n! I. ii". :unl ((aliened, ami \\ed-c :,h.ipcd in Iron I ; of Ihe.ie NIC barm! Hej.'.menl i:t < I. appioa. IK M il;i l< II , . of I he o|>|xisilc , ide in donl, lull, in Hep. ii. ilcd (mm il l>clnnd I. a inc.li.in | i'( <(:;;< of 1 1 ir head ; I lie rtecond ;.c"inenl L| I M.I n - n l.i i in oil I IIIK .1 ecu 1'rolll .il.o . will) (In :I|H ,,l In. IM m I < Icndlll" I.. ,.,n<| Mir oil-in of I lie Mm \ a I apci in" ll:i"i-lliun of .ilx, id il, i|o/,eil He,"inenl;i. The anlennie when icllcxed . I- nd I,. ..ml I he liiMl, Uionieje, .-"111.111 and have llirlii.il I wo liiciil.H Hliorl, and roin|>l eriited, Ihe Ihird Momeu lull longer, I he, r.iiiilh and hllli litii^cr and nrarl\ ('ylindrical, I'nllou cd l.\ a l:i|iin;- lla."( Ilinn ahoiil a ; l.ii" a ; lh< |H'dnnrlr, ii.lid roni|(Mi-d ol lill. . n ID lurnl y ; . - liicnlM. 'I'ln- ma \illiprd . ha\< a IIDI I 1 1 la n" nl.i i < l.inal laini II. i .md a 1 1 \ c (Dinlcd [)alpUH, Of Which I IK In I Mcyini'iil i , JIDI I and 1 1 .m . i > , Ihc. ;;cc(ind IM I i 1.1 n- nl.u and licaii, DM d.i inner a|H-\,a l<-\\ ;(Kc(l H|>in< Ihc. fourth SOgment i.s llallcncd and I nniNV HoinrAV hal cnr\ ed ;,|iine! placed C|DMC !., < MK i The ma nd 1 1 I|CM MiippDi I, il Hlcnder pa I pi i, 4 of I Im < . - mi id H, of Imli MM middle one in Itinch MK IDII-M I , and I he lil,Hl. JH rolninl, :ind hii-KIc, nha.prd, wil h a comb !' :-.hiii I. HpincM alon; 1 I lie. innei curve,. Thin He^iiienl, IICM, in IhcDidinaiv p>. i IK. n pi i ai i IK- bs/BG of tho antenna of DM >n,< Hide,. The, lir;sl, MiDiacic .;e;'inenl. i;-., a I, d, aiileimr mai-'in, He,iil'e,nl y |HD.I>|< i Mian I, lie, head, Iml expand i.i|ndl, l>:i' I .-. a i d. 1 1, in e,X(',ll,Va I cd mlionl, lor I IM- eyes, vvhicJi projccl oine\vhal, beyond I. lie. pi. I. i mr mill ; ,111 '! I lie, In ad. The CCDIM!, Ihird, and loiirlh MIDI:M M X--HH i,l are, eat'li il, Illlle, Hliorlcr Mian Ihc In I, I In hlMi and HJxIli ;ue, nomewhal longer; Ihc - enlli IH Hhorlci Ih.m (In ixlJi. The ( piim ia ol I he, llrnl, UlOI'lteii < mcnl arc, nol ; < paialed ly Hill, lire, lull in I IK < . mid and lollovvin inenl | Ihey ace :;< -p.i i .1 1 <-d, lllld, .pccially on I he, iinh',rior ; . .- im nl , mail.ed v, il h I v D olilii|ii( <|epr<',HH('-d lilM'.H. Till', e.piinera, oT I In .iDiid, llnid. and loiirl.li Meynienl i are, rounded or linneaie liehind, Iml in I. lie, po lenoi c-'iiicnl MK , l.iiDine, aOUto Olid extend Iteyond MK aujdc'iol' MK c-MiKiil ID which I hey ;ire al hidied. The lirnl, Mine p.m .! I are .hoil and aimed \villi Hl.l'Oll^' lioohe.d daelyli. The piopod.d me.nl', an al D cinved, and I, lie, cm'pllH JH Hliorl in UK In I p.m Iml. Dine.-. |,al Ion", i in MK ..olid and Ihil'd pan . Tin UK MI i ..In,., I. < M r"v's Bank, lat. 150 - 1872 1 ':ir k:inl :uul ( 'ooko 1 Alo. 2139 I " II' X., loii. 67 17' W. ColonialMus. Hal- 2 Alo. George's Bank , 1878 [fax. SclMioni-r A 1 irn < 1 3 Alo. . do Codfish May 8 1870 \\ imsim. J I* Slicini-lia 3 Ale do do May 15 ls~'.i (' l|lt .1 O ( .< 1 ' l II 9 Alo. N. K. George's Bank. . 47 ....do Nov. 29, 1878 J. P. Shemelia ;i Alo. 2154 ( 1 ul I'of Maine Skato (Raia) 1878 U S Kisli Coin'n 20 Mr 2156 I '.i i ii 1 1 if 1 1 .1 1 1 . . Halibut 1878 1 \lc- 2157 40-50 Codlish 1878 Schooner liebecca 1 Alo. 2158 Grand Monau Bank 100 1878 Bartlett. Schooner Potor D. 3 Ale. 2155 do . 100 1878 Smith. U. S. Fish Com'n 1 Alo Brown's Bank . 52 Codfish . . Dec. 1 9, 1878 Mr. Isjiat* Butler o Ale. do ....do Feb. 13, 1879 Capt. J. Q. Gctcholl 2 Alo. do 30 do May 1 1879 do g Ale. Liit. 43 25' N., Lon. 180 Halibut Aug. 21, 1879 Capt. S. W. Smith Alo. 60 W. Da vis's Straits do , 1879 and crow. Mr. N. 1*. Scudder . 10 AJo. Syscenua* gen. nov. Eyes wanting; palpus of inaxillipeds two-jointed; sixth and seventh pairs of legs elongated; pleou suddenly narrower than the thorax; pleopods naked. This genus is unfortunately represented in the collection by a single specimen. It differs from JEya by characters that point toward the Cymothoidatj as in the reduction of the segments of the palpus of the maxillipeds, the sudden constriction at the base of the pleon, and the 11:1 Iced pleopods. The absence of eyes, although a conspicuous charac- ter can hardly be regarded as of great taxonomic value. It is separated from the OymotJioidce by the form of the head, which is not produced over the bases of the anteimulco but merely projects slightly between them. The autcimuLe moreover are composed of three peduncular seg- ments and a ilagellum; the basal segments are much smaller than in ^Eya and less flattened, but still form a part of the anterior outline \vhen seen vertically. The last lour pairs of legs differ from the first three, and are more or less elongated and fitted for crawling. The iiropods are distinctly ciliated. Syscenus infelix up. nov. This species may bo recognized among our Isopoda by the possession of the full number of segments, the ciliated uropods, naked pleopods, and the absence of eyes. a messmate. 388 REPORT OF COMMISSIONER OF FISH AND FISHERIES. The body is more than twice as long as broad and only moderately convex. The head is small and as seen from above is transversely somewhat diamond-shaped with rounded angles. It presents in front a slight prolongation between the antennulae, and on each side of the short median process its outline is excavated above the bases of the antemmlfe. The posterior margin is curved, but near each end is a faint indication of a lobe, projecting backward like the ocular lobes in 2Ega, but the eyes are wanting. The antennulse arise near together on each side of the front and are short, extending when reflexed but little beyond the lateral margins of the head and only slightly surpassing the fourth autennal segment. They are readily distinguishable into pe- duncular and flagellar segments, the first three segments being of com- paratively large size and about equal length ; the second segment much flattened below against the antenna;; third more slender than the first two and followed by a short, tapering six-jointed flagellum. The anten- nulse are in their natural position reflexed, the second segment being articulated at an angle with the first. The antennae are considerably longer than the antermula3 and, when reflexed, slightly surpass the pos- terior border of the third thoracic segment. They are inserted below and a little outside of the antennula3. The first segment is short and flattened below; the second is also short, the two together being hardly longer than the basal antennular segment; the third segment is about as long as the first two together, and the fourth is a little longer than the third, but of slightly less diameter; the fifth is more than one-half longer than the fourth, but is more slender and is followed by a slender, tapering flagellum of about twenty-four segments. The last two pe- duncular segments bear a row of elongate bristly hairs along the margin which, when reflexed, is brought next the body, and the row is continued, though with shorter hairs, along the flagellum. The palpus of the maxil- lipeds is composed of two segments of which the first is nearly square and armed at the inner distal angle with a minute hook; the second is bluntly triangular and armed at the apex, which is directed inward, with three booklets. The external lamella is small and subcircular. The outer maxilla? are armed with short hooks at the tip ; the inner with minute denticles. The mandibles are flattened and denticulate at the tip and bear a three-jointed palpus of which the three segments decrease in size to the last. The first thoracic segment is twice as long as the second; its anterior margin is adapted to the head; its posterior margin is nearly straight above and rounded at the sides until the cpirneral region is readied, when a short, pointed projection juts backward, being the tip of the epimeron on each side, here united with the segment. The next three second, third and fourth thoracic segments are of about equal length, and each a little over half the length of the first segment; their pos- terior margins are nearly straight above and rounded at the sides ; the third segment is broadest. The fifth and sixth segments are each a MARINE ISOPODA OF NEW ENGLAND, ETC. 389 little longer than the second; the seventh about as long as the second. The last segment, and in a less degree the sixth and fifth segments, have their posterior margins excavated along the back; all have their lateral angles rounded, although the angles of the seventh segment are but slightly so. The epimera are short and pointed; those belonging to the second and third segments are larger than the following ones, and are applied directly to the lateral margin of the segments; the posterior four pairs of epimera are shorter and smaller, and are separated from the lateral borders of the segment by a fold of the integument cutting off a portion of the anterior lateral angle and increasing in size to the last segment. The first three pairs of legs are alike, distinctly ancoral and directed forward. In each the basis is much the longest segment; the ischium is strongly flexed upon it; the merus is expanded distally around the base of the carpus and bears a few bristles at the outer angle; the carpus is short, less than half as long as the propodus, and the dac- tylus is strong and curved. The fourth pair of legs, like those that follow, is directed backward; the basis is the longest segment and the ischium is strongly flexed upon it and of more than half its length ; the merus, carpus and propodns are each about two-thirds as long as the ischium, and all four segments are armed distally with a whorl of spines around the articulation with the succeeding segment; the dactylus is slender, sharp and curved. The fifth pair of legs is longer than the fourth by a little more than the length of the dactylus, the elongation being in the segments from the ischium to the propodus inclusive. The sixth pair is the longest, being, when extended, as long as the thorax and pleon together. This elongation is confined also to the four seg- ments above indicated, and of these the ischium is about as long as the basis; the merus falls a little short of the ischium in length; the carpus and propodus are of equal length, and are as long as the ischium ; all these segments are slender and slightly curved, and are armed distally and along their inner side with short spiuules. The dactylus is slender and curved. The seventh pair of legs resembles the sixth but is shorter by about half the length of the propodus. The fifth pair does not attain the middle of the carpus of the sixth. The pleon is of less diameter than the last thoracic segment and about as long as the last five thoracic segments. Its transverse diame- ter increases slightly to the base of the last segment, where it is broad- est; the fifth segment is a little longer than the preceding one, and the last segment is of a broad ovate form, acuminate and ciliated at the tip, truncated at the base and smooth above, except for a faint trans- verse impression on each side near the base, and a still more faint im- pressed median line toward the tip. The uropods attain the tip of the telson but do not surpass it ; they have the basal segment oblique but not produced at the inner angle, and bearing two elongate-elliptical 300 KKI'OKT OK COMMISSIONS OK K1HII AND FISHERIES. rami, laperin<, r ai tin-, base and ciliated, Mio inner about one-third longer than (lie oilier. 'I lie |ileo|)od:, are (|lllle naked :IIM| de,,llliile of cilia. LeiM.dli :,'.". ; breadth, ; brea,dfh of pleon 1"""; length of head 3 mm j breadth l.'J""". A single specimen of Mils species was dredt;ed by tlio l^. S. l (1 ish < 'ommi. . ion, :ii)oui tit'iet-ii mile northeast of Oape Cod! } in i *> r.iiiioms brown mud, September 10, IS?!). XI, OTMOTHOID^B. I lend produced anteriorly o\ cr I lie basesof I lie :i n I en nil l;e ; ma \ illipeds fe\\ jointed, operoulifonn i oiandibles palpigerous) moidii snctoriMl; le^s :iini<'(l will) :,lioii" Clll'Vcd c;irni", |\vo thdlened r:nni; Icilnl p;ir:i,sil ie; body ollcn uns} iniiiel ric;d by distort ion in llie .ididl;;. 'liiniiy is represented within our limits by ihi'c'e genera and as iii:in\ ;speei<-s. They :ire p;ir;isilie. in linbit, iisiisdly on ll,sh, nnd li\ tliem- Helves by Ilieir StTODgly-OUrved rlawN to their host, ol'li^n \\ilhin lll(^ nioiil h , or .il.onl I IK- liriinclii.d e:i\ il \ , .111. 1 I rc( [ ucn I I \ become dislorlcd \\lien lidly ^i'o\vn. In .ill our BpeoleS UMI IM'JMI is siiiiill, and lias llu^ .oilenoi iii.ii'-iii produced, concealing (lie b.ises of I lie anliMinnlai and the antenna'. The head is I hreo-lobed behind, and llie lirst (horacie. ; e incut is adapted to it. 'I'lic .inlennid.c and anlenna- are both short and l.ipeuii", \\ilhoid \. Tin- jileon in our i' '.i.- is not suddenly narrower than (he thorax, a,; it i.-i, however, a.l least in I he adnlls, in SOniO genera belonging to Miis family. The se^ineiils of the pleon arc distinct, the last one sent ilorm In li hi-'li'iti ^i-\\ii\{i< I lie HivyiMll li | M 1 1 nl logS ' i 'nil lo I lir i>\ I iviml \ i>l I lir l.nl and itli-nilfi , roin | u c ;i ad . i .1 \\ 1m I, ,, \\ il li .1 i.in:|||, ;ilinii:.| rudnii. nl .11 \ , :.l I .nv. Ill la \\ ." MAKIM: [SOPODA or \r\\ ENG1 \M\ r iv. .'!M ami ol' moderate si.v, not beiui; Ljreatly enlarged. The pleopods are destitute of cilia in the adults. This famih is evidently closelv related to tin' preeedui:: :iiiil m.iv N et have to be united \\ilh it. or ev on be extended so as (o include also (ho ('ir<>l((iiiilir. Our represent at IN es ot' (lit 1 three families are so few dial 1 have had little opportunity to studv the genera. and as before slated. 1 have separated the ("iroltiititlir priuripallv in del i ri < ju i (> to (lu opiui)iis ol' Sclii(tdt(\ Ali'tropHs KilNvanls, Si/stYiins I lanver, and .1-',ititli<>< i l>ana IIKIN bo mentioned as genera pointing toward ft trrtnaitioii i>ci\\tvn tln . / '(//(/(( and Clfinothoidat. and it is <.v parasitism. They h:iNe thus >\ehau: % .ed (lie ainlMilaloiN leus ot' I lie ./,'s( part in se\eu pairs, and have lost (he natatory eilia of the pleopods. Their anlennary organs are also iiiueh l\ss perl'oel than in that tainilx. All these modifications are in the line of the sedentary lite ol' a parasite. The interesting observations of Mr..i. i<\ Uuilar \\i\\v siu>\\n that m eertain genera of the OymothoidCD (GynwikOQ* .V losl bv molting, theovi duel obtains an external openin:;', t he inenbalorv |ioneh is dev>loped, and the animal beeomes a female. Mr. I'.idlar's slatement.s provoked considei'able diseussion, but (hey ha v e recent Iv bt>en venlierrt'ii us tutor Sa,y* (l menhaden (l'>r('roorti front of the head over the bases of !ho anlennary orj^an , and the slron:;ly hooked or ancoral le^'s nro eharaelerisl ie of I he I'amilv, and lli< ^eiuM'a may DO distinguished by ineaiiH ol' the following (able : / ciii:iirii, eyoi Iftrgo oonspiououii ^BgotHon t p. -i'.'n i ropoda< ( iyniniotrlnu.1 ; posterior (^plmcrn olongfttodi AVnu'i/i/, i>. ;t'.M J naked ; uodv \ ( Miri\ niuii'l I'H'ill ; C|IIMII'| :i Nliorl, l,H'<>ii>'< 'i, p ''! N I-IIM 1 1. 1 I . i. li n 1,1-iH'h, Dii-l. Sri. n:il., Imn. \ii, |>. Iti.l, IH|H. r.nd y oval ; head .small ; ev e.'; of modern to ni/,o; posterior I hoi acic incuts and epimera ant;iilaled or Bpinifonn, giving ft sharply .serrated or dentfttod outline to the thorax; Qrst two "abdoniiiuil epimera" also spiniform; pleon of six distinct segments. Our species of \<>'<><'ii. il'.":.. I -IH. 392 REPORT OF COMMISSIONER OF FISH AND FISHERIES. or quite concealed from above by the projecting angles of the segments, and the " abdominal epimera " are mostly concealed beneath the pleon. These organs are the much elongated inferior angles of the segments, which in allied genera, as JEyatlioa, are short and not produced. In a lateral view they considerably resemble the posterior epimera, giving the appearance of two additional pairs. The specimen first described is smaller than others that have since been obtained. Nerocila munda Harger. Nerocila munda Harger, This Report, part 1, p. 571 (277), 1874; Proc. U. S. Nat. Mus., 1879, vol. ii, p. 161, 1879. VerriU, This Report, part i, p. 459 (165), 1874. PLATE X, FIG. 65. This species may be recognized among our Isopoda by the projecting posterior epimera, and the two pairs of spiuiforni "abdominal epimera" beneath the pleon. The body is oval, twice as long as broad, smooth, polished, and mod- erately convex. The head is flattened, broader than long, narrowing anteriorly, broadly rounded or subtruncate in front, three-lobed behind, with the middle lobe largest. The eyes are black and consist of an irregularly rounded patch of small indistinct ocelli, and are visible both above and below. The antennulse are about as long as the head, and composed of eight segments, of which the first is short, the second is the longest, and the remaining six decrease pretty regularly in size to the last. The antennaB are a little longer and more slender than the antemiulce and have the first segment short, the second subglobose, the third, fourth, and fifth cylindrical, and a little larger than the segments of the flagelluni, which are about five in number. The mandibular palpi are longer than any three segments of the antenna, and the first seg- ment is large, the second elongate conical, the third shorter, cylindrical. The first thoracic segment is much longer than the succeeding ones and adapted to the head in front. It is slightly produced at its lateral angles behind, or rather appears so from the union of the epimera, which really constitute the projecting angles to the segment. In the second, third, and fourth segments the posterior angles are but little produced, and are equaled or slightly surpassed by the epimera, but in the last three segments the posterior angles are acutely produced much beyond the epimera of the corresponding segments, the angle of the sixth segment nearly attaining the end of the seventh epimeron. In a lateral view, only the last two epimera are decidedly acute, while those of the second and third segments are obtuse and rounded behind. Seen from below, the posterior angles of the epimera are acute throughout. The first pair of legs are slightly more robust than the second and third ; the last four pairs are still more slender, the last pair longest, and the last two pairs armed with a few short spinules. The pleon is shorter than the thorax and much narrower, though MARINE ISOPODA OF NEW ENGLAND, ETC. 393 not suddenly so and tapers but little posteriorly; the telson is flat- tened, and regularly rounded beliind. The " abdominal epimera" are acute, the second smaller and more slender than the first, but their ex- tension backward varies with the state of contraction of the pleon. The uropods (pi. X, fig. Co a) surpass the telson, and have the inner angle of the basal segment sharply produced. The rami are flattened; the ex- ternal one twice the length of the basal segment, narrowly ovate or lan- ceolate, sometimes slightly curved, and surpassing the telson by half its length. The inner ramus is narrowly oval, obliquely truncate behind and about three-fourths as long as the outer. The length of the specimen figured, which was the one first described, is 15 mm , breadth 7 mrn , but specimens measuring 25 mm in length have since been collected; color brown or greenish, with two narrow dorsal bands of lighter color, most evident at the extremities. The original specimen was obtained on the dorsal fin of Cerato-canthus aurantiacus at Wood's Holl!, Vineyard Sound, in 1871, and two more specimens of larger size have since been obtained, also from Vineyard Sound!, Mass. JE gat ho a Dana. JEgathoa Dana, Am. Jour. Sci., II, vol. xiv, p. 304, 1852. Body elongate oval ; pleon not suddenly narrower than the thorax ; head large, subtriangular ; eyes large ; legs nearly alike throughout, with strong curved dactyli ; epimera of moderate size or small ; pleon long and large, composed of six distinct segments ; pleopods not cili- ated ; uropods more or less distinctly ciliated, rami subequal. This genus is represented in our fauna by a species parasitic in the mouth of a squid. The large, granulated eyes remind one of JEga, and the ciliated uropods also indicate the approximation of this genus to the preceding family. The ciliation is, however, nearly rudimentary in our species, and is present, at least in the young, of other members of the Cymotlioidce. .Slgathoa loliginea Harger. JEgaihoa loliginea Harger, Am. Jour. Sci. , III, vol. xv, p. 376, 1878; Proc. U. S. Nat. Mus., 1879, vol. ii, p. 161, 1879. PLATE X, FIG. 66. The legs all armed with strong curved claws, the large conspicuous eyes and the slightly ciliated uropods serve to distinguish the present species from the other Isopoda of our coast. Body elongate oval in outline, nearly four times as long as broad, slightly dilated near the posterior end. Head broadly rounded in front, subequally, but not deeply, trilobed behind. Eyes large, with evident facets, lateral, semi-hexagonal, visible from below, covering nearly half the area of the head above, projecting posteriorly beyond the middle 394 REPORT OP COMMISSIONER OF FISH AND FISHERIES. lobe of the head. Exteriorly they form about two-thirds of the -lateral margin of the head. Their interior boundary is in the form of three sides of a hexagon, separated at their nearest points by a lit He, more than the transverse diameter of the. eye,. The anli-uimhe an- .about, as long as the head, composed of eight segments and separated at Hie base. The first segment is short and stout ; the, next two a little, longer, but scarcely distinguishable from the following five, llagcllar segments, which decrease in size to the last. The antenna-, are, eomposed of ten segments. They are more slender than the antennuhe, and surpass them by about two segments. The first two segments are, broader than the, following three, which are also somewhat larger than the, five (lamellar segments. The first thoracic segment is shorter than the head, but much longer than any of the sueceeding segments, which to the sixth are of equal length, each about one-third shorter than the first. The sevent h segment is about one- third shorter than the sixth. The fifth and sixth are, broadest, each being about one-third broader than the first. The epirnera do not project behind the angles of the segments to which they are attached. The legs differ but little throughout. The first pair are shortest, and the first three pairs are somewhat stronger than the last four, which are armed with a few scattered short spiuules. The seventh pair are the longest. The pleon is a little longer than the seven thoracic segments. The fifth segment is broader behind than in front, and the last segment is as broad at the insertion of the uropods as the third segment, and is rounded behind. Anterior pleopods with the basal segment nearly square. Tin; uropods are unlike on the opposite sides in the specimen figured. The normal form is probably seen in the right uropod, which surj the telson by less than half the length of the outer ramus. This ram us is longer than the inner, narrow, with nearly parallel sides and is obliquely truncated at the tip. The inner ramus is somewhat diarnond->haped. The ciliation is nearly rudimentary and might be overlooked. The b,i.-al segment is alike on the two sides and has the inner distal angle acute and but slightly produced. Length 13 mm , breadth 3.6 mm ; color in alcohol yellowish, with minute black specks most abundant on the pleon; eyes black, conspicuous. The specimen w*as obtained June 1, 1874, by Mr. S. F. Clark, at Savin Eock !, near Xew Haven, from the mouth of a squid (LoligoPealii), whence the specific name. Two specimens " parasitic on young mullet " are i n the Tale College Museum, collected at Fort Macon !, X. C., by Dr. H. C. Yarrow, which appear to belong to this species, showing that it is not confined to the squid. Livoneca Leach. Liconeca Leach, Diet. Sci. nat., tome xii, p. 351, 1-1-. Head small, projecting in front over the bases of the antennulge. which, like the antennae, are short ; legs all alike and armed with strong curved dactyli; body broad, oval, often obliquely distorted. MARINE ISOPODA OF NEW ENGLAND, ETC. 395 Tliis genus is represented by a single species, in which Hie body is of a broadly oval form ami depressed. All tin; Nigs ;ini short and armed with strongly curved daefyli, and, in the natural posit ion, an-, closely appressed to the ventral surface, which, however, is more or less exposed below along the middle. Livoneca ovalis Wliito (Say). Cymothoa ovaUe Say, Jour. Acad. Nat. Sci. 1'hil., vol. i, p. if'.M, 1818. DcUiiy, Zool. New York, Cnmt., p. <1H, 18-14. Livoneca ovaUs "White, Cat. CriiHfc. Brit. MIIH., p. 101), 1847. (lAnmcca). llargcr, This Rcporf, purl i, p. 572(278), pi. vi, lig. 29, 1874; Proc. U. 8. Nat. MUH., 1871), vol. ii, p. 102, 187'J. PLATE XI, Fi<;. (\1. The broadly oval, more or less distorted and unsymmefrical form of this Isopod serves to distinguish it from any other species yet rccog ni/ed within our limits. Body broad, oval, usually oblique, arid not, as represented in part I of this report, pi. VI, fig. 21), with the, sides of equal length. The, legs, moreover, in that figure are in an unnatural position, as fhey are, dur- ing life, concealed beneath the body of the, animal and appressed to the ventral surface,, the first three pairs directed forwards and the hist four pairs backward. The, dorsal surface is moderately convex. The head is small, rounded in front, trilobed behind, the middle, lobe much the larg- est, the two lateral lobes extending beyond the eyes, which are not con- spieuoiis, small and broadly separated. Antennnhe (pi. XI, fig. <>7) widely separated at the, base,, with the first segment short and stout; the Keeond longer and somewhat lapering; flu; third about as long as the first. These peduncular segments are somewhat flattened. The, llagel- lum is longer than the peduncle, tapering and five-jointed, curved back- ward in the natural position, each segment bearing a row of short blunt sct:e, near the distal end, on the inner curve,. The antenna) (pi. XI, fig. (57/>) are about as long as the, antennuhc, with the first two segments short and stout, the next three more slender; (lagellnm three, or four jointed, with the last segment imperfectly divided and tipped with a few short setae. The maxillipeds are narrow, with the, outer lamella partially united to the basal segment and the, palpus tapering and two- jointed, tipped with a few short curved set:e, at least in young individ- uals. The mandibles are pointed; their palpi (pi. XI, fig. 07 c) tapering from Hie base and composed of three segments of about equal length, the, first subquadrate, the second tapering, the third nearly cylindrical. The, first thoracic segment is longest; the next three a little shorter and about equal; the fifth and sixth still shorter; the seventh shortest measured along the median line, which is usually a curved line except in young specimens. The anterior margin of the; first thoracic seg- ment is adapted to the posterior margin of the head and presents three sinuses, t he middle, one, largest, for the median lobe, of the head, and two smaller ones for the, ocular lobes. The posterior margin of this segment is strongly convex backward throughout. In the succeeding segment^ 396 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. tliis convexity rapidly diminishes so that the fourth has nearly a trans- verse margin and the last three segments become concave behind in an increasing degree. The epimera are narrow and obtusely pointed behind, and do not surpass the posterior angle of the segment to which they are at- tached except in the last two segments. The first pair of legs (pi. XI, fig. 67 d) are short and stout, the basal segment large but short; the next three segments short and with little motion on each other; the propodus stout and somewhat curved ; the dact.vlus long, curved, and strong. The second and third pair of legs are much like the first, as are the four suc- ceeding pairs, but somewhat larger and longer. The seventh pair (pi. XI, fig. 67 e) have the basal segment about twice as long as in the first pair, and the succeeding segments are also proportionally longer than in the first pair, except the dactylus, which is slightly weaker and not longer than in the first pair. The pleon tapers rapidly at the sides ; its first five segments are sub- equal in length ; the last segment forms about half its length, and is flat and broadly rounded behind. Uropods (pi. XI, fig. 67 f) surpassing the telson with the basal segment, about as long as the rami and but little produced at its inner angle; outer ramus linear oblong, rounded at the end ; inner ramus shorter and broader, oblique at the tip. Length 17-22 mm , breadth 10-12 mm . These animals when preserved in alcohol are of a leaden color, with the posterior margins lighter. They are often parasitic on the blue-fish (Pomatomus saltatrix Gill). The details figured on plate XI are from small specimens collected on young blue-fish at New Haven!, by Mr. F. S. Smith. Other localities are Thimble Islands!, Long Island Sound; Vineyard Sound!, Fish Commis- sion 1871, one specimen among scup (Stenotomus argyrops Gill). A specimen was sent to the Museum in 1878, collected by Dr. T. H. Bean, from the gill of Micropogon undulatus caught at Norfolk !, Va., July 9, 1878. Specimens examined. Number. Locality. Parasitic on When col- lected. Received from "3 03 ft CO "> a M <0 a o fc Dry. Ale. Norfolk, Va Micropogon Blue-fish. . .. July 9,1878 T. H. Bean 1 15 1 1 Ale. Ale. Ale. Ale. Ale. Ale. Ale. 2071 2072 2073 2074 2075 2076 New Haven F. S. Smith Vineyard Sound do ,1871 Aug. 17, 1871 U.S. Fish Com do do .. Scilp Vineyard Sound Blue-fish Sept. 2,1871 tT. S. Fish Com F. H. Bradley 1 1 XII. ANTHUEID^E. Body elongate, cylindrical; mouth suctorial; legs ambulatory and pre- hensile, the first pair enlarged; first pair of pleopods thickened and crustaceous, protecting the following pairs ; uropods articulated at the sides of the last segment, standing in a more or less vertical position and forming with the telson a sort of cup or flower at the end of the body. MARINE ISOPODA OF NEW ENGLAND, ETC. 397 This family is represented within our limits by three species belong- ing to as many genera, which, in addition to the characters given above r agree further in the following particulars : The body is elongated and vermiform, often more than ten times as long as broad, and of nearly uniform size throughout. The head and thoracic segments are all dis- tinctly separated from each other, and the head and last thoracic seg- ment are shorter than the intervening segments, which are subequal. Both pairs of antenna are approximate at their bases, and the lower pair or true antennre are short, not greatly surpassing the head in length. These organs have the basal segment short, the second segment flat- tened internally and adapted to its fellow of the opposite side, while above and externally it is excavated for the basal segment of the anten- nuloB. The mandibles are palpigerous, and the mouth parts are fitted for piercing and for suction. In the first pair of legs the first, second, and penultimate segments are enlarged and thickened; the two intervening segments, merus and car- pus, are short ; the dactylus forms a curved finger tipped with a stout spine and capable of complete flexion on the robust propodus. In one or two of the succeeding pairs of legs the propodus may be slightly en- larged. The first three pairs of legs have the carpus, or antepenulti- mate segment, triangular, and their basal segments are directed strongly backward. In the last four pairs the carpus may be short, but is not triangular, and always distinctly separates the merus from the propodus j they are so articulated to the body that their basal segments are directed forward. The first three pairs of legs are articulated to the anterior part of the segment to which they belong, the next three near the middle of the corresponding segments, and the last pair near the posterior margin of the last segment. The pleon is short, with the segments more or less consolidated, and the pleopods are of the normal number and form. The " operculum" is not formed as in the Idoteidce and Arcturidce of the uropods, but is nothing more than the enlarged and thickened first pair of pleopods, the greater part of it being formed of the external lamella, while the uropods have an entirely different and peculiar structure. They are birainous, and con- sist on each side of a more or less elongated, flattened, basal segment, so articulated as to lie alongside the telson, and bearing at the apex a terminal plate, the inner ramus, in the same plane with itself, while, on its upper side near the base, stands a more or less perpendicular, oval plate, the outer rainus. The telsou is directed obliquely downward, and, with the uropods, forms a ciliated cup-like or flower-like termination of the cylindrical body, whence the name Anthura, from the Greek avftos, a flower, and oupd, a tail. The structure of the mouth in this family has been investigated by Prof. J. C. Schiodte, to whose original papers in the Naturhistorisk Tidsskrift I have not had access. The paper on Anthura is translated and partly condensed in the Annals and Magazine of Natural History, 398 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. where that author states that " next the GymothoidcBj though as a type of a separate family, the genus Anthura must be placed." The species of this family may be at once recognized by the peculiar cup-like termination of the body. This cup or "flower" is formed by the telson below, and the uropods at the sides and above ; the outer rarni of the latter organs being placed nearly vertically, and approach- ing each other on the median line above, where, however, the "flower" is more or less imperfect. Our three genera may be distinguished as follows : First five segments of pleon consolidated above, Anthura (p. 104) ; segments of pleon distinct, antennae and auteunulae subequal, ParantJiura (p. 108) ; segments of pleon distinct, antennulse greatly enlarged in the male, Ptilanthura (p. 111). Anthura Leach. Anthura Leach, Ed. Encyc., vol. vii, p. "404" (Am. ed., p. 243), "1813-'14." Antennulae and antennae short, subequal ; thoracic segments not separated by constrictions ; pleon with the five anterior segments con- solidated above and resembling the last thoracic segment. Our species of Anthura appears to agree in all generic characters with A. gracilis Leach upon which the genus was founded. In A. polita, how- ever, the consolidated portion of the pleon is seen at the lower part of the sides to be composed of five consolidated segments, and bears the normal number of pairs of pleopods, while Bate and Westwood* say that " the four anterior segments are soldered closely together " in A. gracilis, and that " the pleopoda consist of, at least, four pairs of oval plates, strongly ciliated, on each side of the ventral surface of the basal seg- ments of the tail." They had not, however, fresh specimens of the spe- cies, which is evidently closely related to ours. The incubatory pouch of the females in the genus is confined to the third, fourth, and fifth segments, and is composed of three pairs of lamellae, which overlap from behind forward, while the anterior margins of the first pair are united to the anterior part of the third segment. Anthura polita Stiinpson. ? Anthura gracilis Dekay, Zool. New York, Crust., p. 44, pi. ix, fig. 34, 1844 (not of Montagu and Leach). Anthura polita Stimpson, Proc. Acad. Nat. Sci. Phil., vol. vii, p. 393, 1856. Harger, Proc. U. S. Nat. Mus., 1879, vol. ii, p. 162, 1879. Anthura brunnea Harger, This Report, part i, p. 572 (278), 1874. Verrill, This Report, part i, p. 426 (132), 1874. PLATE XI, FIGS. 68 and 69. This species is distinguished among its allies on our coast by the nearly complete union of the basal segments of the pleon, which have together the appearance of an eighth thoracic segment. The cup or "flower" at the end of the body serves to distinguish it from other Isopoda. * British Sessile-Eyed Crustacea, pp. 157 and 160. MARINE ISOPODA OF NEW ENGLAND, ETC. 399 The body is smooth, shining and flattened above and broadly keeled, in the males below. The head is a little broader than long, deeply ex- cavated on each side of the front for the bases of the antennulae, and produced at the sides. The eyes are small and lateral but distinct, and are placed on the outer side of the anterior prolongations of the head, about on a line with the bases of the autennula3. They are too indistinct in the figure, and the eye was even omitted on the right side by the en- graver. The antennulae (pi. XI, fig. 68 a) consist of a tapering three- jointed peduncle and a very short flagellurn. The first peduncular seg- ment is the largest, and is flattened above and on the inner side ; the second segment is smaller, cylindrical, and provided with a comb of hair- like seta3 along its outer side ; the third is smaller and shorter than the second; the flagellum consists of a single very small segment, with indications of a rudimentary second segment at the end, where it is also tipped with setae. The antennae (pi. XI, fig. C86) consist of a five-jointed peduncle, and a short flagellum much like that of the antennulae. The basal segment of the peduncle is short; the second segment is the largest and is of peculiar shape, being excavated on the outer side to adapt it to the antennula. which lies in the groove thus formed, while the segment is bent upward and inward, and exposes a slender triangu- lar area' with the point backward, between, and on a level with, the an- tennulae ; the next three segments are sub-cylindrical and diminish in size, and are followed by one or two small flagellar segments tipped with setae. The maxillipeds (pi. XI, fig. 69a) are thick and strong, and are com- posed of a basal quadrate segment, a Little longer than broad, with its proximal external angle elided for the short, sub-triangular external lamella, and bearing two segments representing the palpus. Of these segments the first is but little smaller than the basal segment and is sub-quadrate, tapering a little at the sides beyond the middle. The terminal segment is straight at its articulation with the preceding, and nearly so along the inner side, then rounded in the remainder of the out- line. The segments of the palpus are finely ciliated along their margins, except along the external margin of the first segment, where the cilia- tion nearly disappears ; they are also provided with coarse setae, a few of which occur on the maxilliped, near the outer distal angle. The inner maxilla (pi. XI, figs, 69 & and &') is rather robust, and terminated by a strong tooth or spine, below which, on the inner side, is a row of smaller curved teeth. The mandibles are terminated by a horny tooth, below which is a serrulated lobe ; the mandibular palpus is robust ; the second segment much the longest and provided with stout setae ; the last segment with a comb of rather short setae. The maxillipeds are of much firmer texture than the other parts of the mouth. The first thoracic segment is the longest, and is closely adapted to the head behind so as to allow but little motion. The second segment is shorter but somewhat broader than the first, and is rather freely 400 REPORT OF COMMISSIONER OF FISH AND FISHERIES. articulated with it, and still more freely with the third; it is car- inated below, but its articulations are much less free than in the next genus. The third, fourth and fifth segments are each about the length of the second ; the sixth and seventh are progressively shorter. The first pair of legs (pi. XI, fig. 68 c) are quite robust and have but little free- dom of motion, being directed forward under the head and hardly capa- ble of further lateral extension than is shown in the figure of the animal. The basis and ischiuni are large and articulated so as to form a curve, bringing the legs forward ; the merus is short ; the carpus is triangular and extends along the side of the thickened propodus for about half its length, projecting like a tooth at the end ; the propodus is ovate, much thickened and armed with a tooth near the middle of the palmar margin, along which it is ciliated, as is also the carpus; the dactylus is short and stout and tipped with a slender, curved, chitinous claw about as long as the dactylus itself. The figure (pi. Xf, fig. 68 c) represents the inner surface of the leg, the merus being much less conspicuous on the outer side. The second and third pairs of legs are nearly alike and much more slender than the first pair. One of the third pair is represented on plate XI, fig. 68 d. In both these pairs of legs the carpus is small and triangular and wedged in between the merus and propodus, whjch meet above ; the merus is a little larger in the second than in the third pair, and in both pairs it is provided with a few setae at the upper distal angle and along the opposite or palmar side, where the carpus is also armed with setje ; the dactylus bears a few very short set3. The re- maining pairs of legs are rather more slender than the second and third, and the merus is separated from the propodus above by the carpus, which is, however, short. These legs are somewhat hairy, like the pre- ceding pairs. The anterior part of the pleon (pi. XI, fig. 6S#), consisting of the first five segments consolidated, appears much like an eighth thoracic seg- ment a little longer than the seventh ; traces of the sutures between the segments can be seen at the sides. The last segment is distinctly articulated, a little elevated dorsally, where it is also somewhat hairy;: at the lower part of the sides it is covered by a slightly projecting lobe of the preceding segment, which extends over the proximal part of the basal segment of the uropods. Distally the terminal segment is depressed at a steep angle, and is in the form of a plate, ovate and: ciliated at and near the tip, where it is obtuse; the sides are nearly parallel, and it is surpassed by the uropods, which consist, on each side, of a large basal segment, cariuated on the outer side and toothed, at the articulation with the outer ramus, obliquely truncated at the end, where it bears a short, obtusely-triangular, ciliated, inner ramus, , or lamella, in the same plane as the basal segment. The outer ramus, or lamella, forms nearly a right angle with the basal segment, and stands upon its superior outer margin. This ramus is elongate reniform in out- line, being notched below for the tooth on the basal segment, and is MARINE ISOPODA OF NEW ENGLAND, ETC. 401 ciliated along its free superior margin. The first pair of pleopods (pi. XI, fig. 68 e) are composed on each side of a short, quadrate basal segment supporting two rami, of which the outer is, like the basal seg- ment, of firm texture, and acts as an operculum ; in shape it is semi- oval, with the inner ma'rgin nearly straight, and is ciliated distally, and along the outer margin. The inner ranius is much smaller than the outer and of delicate texture, and, in the natural position, is covered and concealed by the outer ramus; it is slender, with nearly parallel sides, rounded at the tip, and not ciliated. In the males the second pair of pleopods (pi. XI, fig. 68/) bears, near the middle of the inner margin of the inner ramus, a slender stylet, slightly surpassing the lamella to which it is attached. The lamellae forming the incubatory pouch of the females are of con- siderable antero-posterior dimensions, and the posterior widely overlap the anterior ones, while the anterior border of the first lamella is united with the third thoracic segment, to which the lamella belongs. Length 15-18 mm ; breadth 1.8-2 mm . The color is brownish above, mottled with yellowish or honey color, lighter underneath. This species was described as new by the present author in the first part of this report under the name A. brunnea, but there appears to be no sufficient reason for regarding it as distinct from Dr. Stiinp- son's A. polita. It is apparently closely related to A. gracilis Leach, although sufficiently distinct according to Bate and Westwood's* de- scription and figures. Those authors, however, seem to have had but very poor and imperfect material on which to base their work. They figure and describe the telson and uropods as truncated and crenulated, and Montagu,t in his original description of the species, says that " the body is terminated by five large caudal appendages truncated at their ends." Kroyer's $ descriptions and figures of A. carinata approach much more closely to the present species. His figure of the antennula considerably resembles ours, but in his description he gives as the relative lengths of the four segments composing it 11, 4, 3 7 5. In our species the last or flagellar segment is much the shortest, as may be seen by the figure, plate XI, fig. 68 a. He further speaks of the telson as crenulated, while it is entire in A. polita, and his figure (Voy. en Scand., pi. 27, fig. 3n') shows no tooth-like projection or angle on the basal segment of the uropods, as seen in a lateral view, and the corresponding margin of the outer or superior plate is destitute of the notch shown in the lateral view of these organs on plate XI, fig. 68 g. The inner ramus or lamella of the first pair of pleopods is also figured as much larger and more expanded distally than in our species, for which see plate XI, fig. 68 e. Unfortunately I have had no European specimens for comparison. *Brit. Sess. Crust., vol. ii, p. 160, 1868. t Trans. Linn. Soc., vol. ix, p. 103, pi. v, f. 6, 1808. tNaturhist. Tidssk., II, B. ii, p. 402, and Voy. en Scand., Crust., pi. xxvii, fig. 3a-0, 1849. 26 F 402 REPORT OF COMMISSIONER OF FISH AND FISHERIES. This species was described by Dr. Stimpson from specimens taken at Norfolk, Ya., and has since been collected by Professors Smith and Yer- rill at Great Egg Harbor!, N. J., in 1 fathoms shells and mud; by the U. S. Fish Commission in Long Island Sound!, especially at Noank Harbor !, among eel-grass (Zoster a marina) and mud ; off Block Island ! in 17 to 19 fathoms sand, mud, and stones ; at Yineyard Sound !, at low water and in sand, and in 1878 at Gloucester !, Mass., in mud and among algae. Specimens examined. CM O to ft 1 Locality. o> o Bottom. WTien col- lected. Received from Jj Dry. Ale. 1 1 3 p< to & fc 10 GrefttEgg Harbor N.J. 14 Shells and mud Apr. 1871 Smith &Verrill Ale. 2077 Koank Harbor, Conn . . Eel-grass Aug. 28, 1874 U.S. Fish Com. 2 Ale. 2078 do Mud and eel-^rass Aug. 29 1874 do 2 Ale. 2079 do Mud Aug. 28 1874 .do 2 Ale. 2080 Vineyard Sound L. w Siind Sept. 8 1871 ..do 2 Ale. Squan Estuary Glou- Mud , 1878 ... -do 2 Ale. cester, Mass. Gloucester Mass Mud and algse , 1878 do 1 Ale. Paranthura Bate and Westwood. % Paranthura Bate and Westwood, Brit. Sess. Crust., vol. ii, p. 163, 1866. Pleon articulated, composed of six segments; thorax deeply con- stricted at each end of the second segment ; antennulae and antennae subequal; palpus of maxillipeds three-jointed; inner maxillae acicular. The first character given above is the only one given by Bate and West- wood, who, however, mention that the pleon bears the normal number of pleopods; a character that would not distinguish our species from the other genera. The distinctly articulated flagellum of the antennulae is provided with a partial whorl of bristles, which, however, forms only the most rudimentary approach toward the structure of those organs in the males of the following genus. The segmentation of the pleon is indis- tinct in the dorsal region, but is apparent at the sides when seen from above, and the pleon does not at all resemble an additional thoracic segment as in Anthura. Both pairs of antennae are provided in our species with a distinctly articulated flagellum, and are of nearly equal length. Paranthura brachiata Harger (Stimpson). Anthura bracliiala Stimpson, Mar. Inv. G. Manan, p. 43, 1853. Verrill, Am. Jour. Sci., III, vol. v, p. 101, 1873; ibid., vol. vii, pp. 42, 411, 502, 1874 ; Proc. Am. Assoc., 1873, pp. 350, 357, 1874 ; This Report, part i, p. 511 (217), 1874. WMteaves, Am. Jour. Sci., Ill, vol. vii, p. 213, 1874 ; Further Deep-sea Dredging, Gulf of St. Lawrence, p. 15, "1874." Harger, This Report, part i, p. 573 (279), 1874. - Smith and Harger, Trans. Conn. Acad., vol. iii, p. 16, 1874. Paranthura brachiata Harger, Proc. U. S. Nat. Mus., 1879, vol. ii, p. 162, 1879. MARINE ISOPODA OF NEW ENGLAND, ETC. 403 PLATE XI, FIG. 70. The deep constrictions, by which the second thoracic segment is sepa- rated from the first and third, serve to distinguish this species from the allied forms on our coast, and the "flower" at the end of the pleon dis- tinguishes it from other Isopoda. Body moniliform, with evident segments; head narrower than, and about half as long as, the first thoracic segment, flattened and quadrate above, with a groove behind a raised anterior border, wedge-shaped below, deeply emarginate on each side of the projecting front above for the bases of the antennulse 5 eyes lateral, not conspicuous, extending behind the emarginations. Antennulse (pi. XI, fig. 70 ) with the first segment large but longer than broad, flattened above ; second and third segments cylindrical ; flagellum of twelve or more segments in adult specimens, with the first segment short, second twice as long and the longest segment of the flagellum, which tapers from the second segment and bears on the distal end of each segment an imperfect whorl of hairs. The antennae (pi. XI, fig. 70 b) slightly surpass the antennulse. They have the first segment short; the second flattened on the inner side, where it is usually in contact with its fellow of the opposite side, and excavated on the outer side above to accommodate the basal segment of the anten- nulse ; the third segment is short ; the fourth and fifth longer and cylin- drical. The flagellum consists of about twelve segments, tapers from the base, and is somewhat hairy. Both the antennae and anteunulse are a little less developed and have one or two less segments in the females. The maxillipeds (pi. XI, fig. 70 c) are elongated, with a short, oval external lamella, and a two-jointed palpus. The large basal seg- ment of the maxilliped projects on the inner side nearly to the end of the first segment of the palpus. The palpus has its segments of about equal length and provided with a few scattered bristles. The inner maxilla3 (pi. XI, figs. 70 d and d') are evident at the tip in an under view of the head ; they are elongate and acicular, and minutely and sharply retro-serrate toward the tip. The three-jointed palpus of the mandibles is also conspicuous below; all three of its segments are short, and the last, which lies ordinarily between the bases of the an- tennae, is flattened, oval, and provided with the usual comb of seta3. The thorax is somewhat flattened above, cariiiate anteriorly below, and has the last segment much the shortest. The first segment is wider than the head and about twice its length, and is more closely united with it than are any of the thoracic segments with each other; it is strongly carinate below, especially on its anterior part, where the carina ends in a prominent tubercle ; a much more slender carina bounds the flattened dorsal portion laterally. The second segment is separated from the first by a deep constriction, and is articulated so as to allow considerable motion, especially in a vertical plane; its antero-lateral angles are prominent in the form of low, rounded tubercles, and be- 404 REPORT OF COMMISSIONER OF FISH AND FISHERIKS. tween them are two less evident tubercles on the front margin of the segment; the dorsal surface tapers behind, and is bounded laterally by carinre; below, the segment is wedge-shaped, but not carinated; behind, it is separated from the third segment by a constriction not quite as pronounced as that in front. The third segment presents two rather more evident median tubercles in front on the dorsal surface, which is defined laterally by carinte, fading away at about the middle of the segment ; below, it is wedge-shaped and carrnate in the males, but membranous along the median line in the females, as are the remaining segments more widely in that sex. In the males they are hard and chitiuous throughout, rounded and scarcely wedge-shaped. The fourth segment is slightly longer than any of the others, and bears, near the anterior end of its dorsal surface, an oval depression with slight elongated elevations at each side. A similar structure occurs on the fifth and sixth segments, which are of decreasing length. The seventh is much the shortest thoracic segment, not being longer on the median line than the head ; it is somewhat produced laterally. The first pair of legs (pi. XI, fig. 70 e) are not as stout as in Anthura polita, and are more flexible ; the carpus is the shortest segment, and is triangular, broader than long; the preceding segment, or merus, shows but little in an external view, but is more evident in an inner view, as shown in the figure, and is much broader than long; the pro- podus is much swollen proximally on its anterior or upper side; im- mediately in front of the end of the carpus it bears a stout tooth ; the dactylus is strong, and tipped with a curved claw. In the second and third pairs of legs the carpus is triangular, but in the posterior pairs it is more elongated so as to distinctly separate the merus from the propodus. The pleon is short, the telsou triangular, acute at the apex. Uropods with the basal segment strongly carinate externally, terminal plate acutely triangular, proximal superior plate oval, curved and attached by its side, nearly meeting its fellow of the opposite side above. First pair of pleopods (pi. XI, fig. 70/) with the external ramus semi-oval ; internal ramus less firm in texture, ligulate, ciliated distally. Second pair of pleopods in the males (pi. XI, fig. 70 g] furnished with a slender stylet articulated at about the middle of the inner, posterior, lamella, ind extending beyond its end. Both the lamellae are crossed by a trans- rerse suture just beyond their middle, at the point where the stylet is Uttached to the inner one. Length 28 mm ; breadth 2.2 mm ; females about one-third smaller. The ;olor is usually light yellowish brown, or sometimes somewhat darker, Kit not as pronounced as in the other members of the family, and nearly c;he same throughout. From P. norvegica G. O. Sars* our species is distinguished by the eyes, which, though inconspicuous, are present. It lacks the tubercle de- * Ckr, Virt. Selsk. Fork., 1872, p. 88, 1873. MARINE ISOPODA OF NEW ENGLAND, ETC. 405 scribed and figured by Heller on the head of P. arcticaj and the flagel- lar segments of both pairs of antennae distinguish it from P. costana Bate and Wrstwood.J This species was dredged by Dr. Stimpson "on a shelly and some- what muddy bottom in twenty fathoms off the northern point of Duck Island," Bay of Fundy. It is rare south of Cape Cod, but was taken in Vineyard Sound ! by the Fish Commission in 1871 ; also on St. George's Bank!, in 110 fathoms, mud and sand; Gulf of Maine!, down to 115 fathoms; Bay of Fundy!, down to 80 fathoms on muddy, shelly, and sandy bottoms; and off Xova Scotia!, 59 fathoms, pebbles, sand and rocks, and at other localities as detailed below. It was dredged by Mr. AYhiteaves in 200 fathoms in the Gulf of Saint Lawrence, between Aiiticosti and the mainland of Gaspe". Specimens examined. Number. Locality. Fathoms. Bottom. When col- lected. Received from Number of specimens. Dry. Ale. Viin-vanl Sound 1871 U.S. Fish Com Alo 2 18] Gulf of Maine, cast from 115 Gravel .. 1877 .. do 2 Alo 2082 13C5 < ';ipr Ann 14n miles. Gulf of Maine, sout li.-ast J east from Capo Ann 13 miles. Cult cif Maine, near Brown's I'.auk. Geor"v's Hank . .. 53 82 110 Mud and stones. Rocks and bar- nacles. Brown mud ,1878 ,1877 187 ....do ....do Packard and 1 2 2 Alo. Alo. Ale 2083 Gulf of Maine, off Ports- - . Soft mud 1671 Cooke. IT S FishConi 3 Alo 2084 mouth -"-' to -J8 miles. Gulf of Maine 65 Mud, sand, and ._ ig-.l do 2 A In, 2087 Casco Bay, 20 miles 68 gravel. Mud Au"- 1 1873 do 1 Alo 1088 southeast of Cape Elizabeth. Gulf of Mann 1 -1 miles 90 Aug 26 1873 do 1 Ale oil' Portland. > llav 1873 do 10 Alo 2086 Gulf of Maine, 17 miles 72 Brown mud 1873 do 3 Ale. 2095 southeast of Monhcgan Island. East port, Mo 1870 A. E Verrill 1 Ale 20 n do 1872 U.S.FishCom 4 Ale 2091 I'.av of Fundv between 60 Mud Aug 16 1872 do g Ale ' 1 Harbor and Wolves. ( in Head Harbor 75-80 Sand and shells 1872 do 8 Ale. g . * i f Fuudy 1872 do 1 Ale of pereiopods normally present, only four are developed in the Guathiidae. The family is thus remarkable in the order both for the transformations undergone in its development, and for the retention after all of an embryonic feature. ITaving discarded the names Anceus and Praniza for reasons given below, I have also rejected the family name Anceidce and substituted for it a name, suggested by Bate and Westwood and derived from that *Ann. Sci. nat., IV, torn, ix, p. 106, 1858. tZeit. Wiss. Zool., xx, taf. vii, figures 24 and 25. 410 REPORT OF COMMISSIONER OF FISH AND FISHERIES. of the typical genus. The name Anceidce should perhaps be restored in case Risso's species should not prove to be congeneric with Gnathia termitoides Leach, Cancer maxillaris Montagu.* Gnathia Leach. GnatMa Leach, Ed. Encyc., vol. vii, p. "402" (Am. ed., p. 240), "1813-14." Praniza Leach, MSS. Anceus Risso. Crust, de Nice, p. 51, 1816. Head very large and quadrate in the male, smaller and subtriangular in the female; first pair of legs operculiform in the male, subpediform in the female; pleon much narrower than the thoracic segments, with nearly parallel sides, and a sharply triangular telson. The name Anceus Risso, which has been used by modern writers for this genus, ought, according to all rules of priority, to give way to Gnathia Leach, as acknowledged by Bate and Westwood,t who, however, hesitated to restore the name on account of Kirby's coleopterous genus Gnathium. While the undoubted priority of the name is a sufficient reason for its re-establishment, it may be worth while to add that Gnathia was not restricted by Dr. Leach to either sex alone, as that author had the sagacity to "suspect that Oniscus coeruleatus Montagu [Praniza coeruleata Desin.] was the female" of Gnathia, and, as far as I am aware, did not publish a generic name for the Praniza-form, although the name Praniza was used by him as a manuscript name, and as such appears to have been published by Latreille in the Encyclopedic M^thodique, which I have not been able to consult. Gnathia cerina Harger (Stimpson). Praniza cerina Stimpson. Mar. Inv. G. Manan, p. 42, pi. iii, fig. 31, 1853. Packard, Mem. Bost. Soc. Nat. Hist., vol. i, p. 296, 1867. Verrill, Am. Jour Sci., Ill, vol. vi, p. 439, 1873; vol. vii, pp. 38, 41, 411, 502, 1874; Proc. Am. Assoc., 1873, pp. 350, 354, 358, 362, 1874. Anceus americanus, Stimpson, Mar. Inv. G. Manan, p. 42, 1853. Gnathia cmna Harger, Proc. U. S. Nat. Mus., 1879, vol. ii, p. 162, 1879. PLATE XII, FIGS. 75-79. It will be convenient first to describe the male of this species and then the female and larval forms. The powerful and prominent jaws in front of the large quadrate head of the males of this small Isopod serve to distinguish it from any other on our coast. The shape of the body is well described by Dr. Stimpson, as " regu- larly rectangular, abruptly narrowed at the commencement of the abdo- men, which has the appearance of another very small rectangle set into the first, and of only one-third its width." It is somewhat bristly hairy, and much tuberculated and roughened above, especially on the lateral portions of the head and on the anterior thoracic segments. The head is broader than long, depressed medially in front and produced into a rounded lobe between the projecting upturned jaws. The eyes are small * Trans. Linn. Soc., vol. vii, p. 65, pi. vi, fig. 2, 1804. tBrit. Seas. Crust., voL ii, p. 169. MARINE ISOPODA OF NEW ENGLAND, ETC. 411 and placed well forward at the sides of the head. The antennuloe (pi XIT r fig. 76 a) are shorter than the head and slender, sparingly hairy, with a short, few-jointed flagellum. The anteunse (pi. XII, fig. 76 6) are also slender, with the first segment apparently composed of two united ; the second segment short ; the third and fourth longer, nearly cylindrical and followed by a slender few-jointed flagellum. The jaws (pi. XII, fig. 76 c) are elongate and turned upward at the apex, irregularly and bluntly toothed near the base within, and somewhat carinate on the outer side near the middle, the carina ending rather Suddenly in a tooth-like pro- cess of the jaw as seen from above. The under surface of the head is deeply and broadly grooved longitudinally, and this groove is covered by what appear to be the transformed first pair of thoracic legs (pi. XII, fig. 76 d). They are in the form of a semi-oval plate on each side, attached near the base of the external side and strongly convex and ciliated on the inner side, where they overlap. This plate is truncated at the apex, where it bears a small oval lamella ; on the surface of the large plate are three large, oval, semi-transparent areas. Within these plates is another pair of organs, consisting of a large basal segment and an artic- ulated series of four flattened ciliated segments. These may be regarded as the maxillipeds, with a four-jointed palpus. The first thoracic segment is indicated above only by a faint sutural line near the posterior margin of the large head. It is followed by five very distinct segments, of which the first two are perhaps most distinct, short, and strongly tuberculated, especially along their posterior mar- gins. The third free segment is broader than the second, square at the sides, with two broad lateral elevations. The fourth free segment is somewhat rounded in front, with its chitinous integument apparently not calcified along the median line. The fifth free segment is narrower than the preceding and produced at the sides around the small last thoracic segment and the base of the pleon. The legs are nearly alike through- out, somewhat hairy and spiny. The pleon is slightly dilated at the middle, with the angles of the segments salient. The last segment is acutely triangular, ciliate behind, surpassed by the uropods, which are also ciliated with a few bristles ; both rami are slender, the inner a little broader than the outer. The pleopods (pi. XII, fig. 78 e) consist of two slender elongate lamella, the inner longer than the outer, attached to a basal segment and not ciliated in the adults of our species. Length 4.4 mm ; breadth 1.3 mm ; color dirty yellowish brown above, lighter below. This form is Anceus americanus Stimpsou. The adult female (pi. XII, fig. 77) differs from the male principally in the following characters : The body is smooth and tapers behind and before, but is much swollen medially, where the segmentation becomes obscure, and the thoracic region seems converted into a sack for the reception of the eggs, plainly to be seen through the transparent integu- ment. The head is comparatively small and sub triangular, emarginate 412 REPORT OF COMMISSIONER OF FISH AND FISHERIES. in front. The eyes are placed farther back, and the large conspicuous jaws are wanting. Under the head, the first pair of legs (pi. XII, fig. 78 a) are slender, three -jointed with a minute terminal segment, and lie upon a delicate membranous plate on each side ; within these are a pair of organs resembling what I have regarded as the maxillipeds of the male. The first two free thoracic segments are short and curved some- what around the head; the next two segments are much enlarged and nearly coalescent, and the fifth free segment is nearly similar in form to that of the males. The last thoracic segment is short and small and, as in the male, resembles a segment of the pleon. Thepleon (pi. XII, fig. 78 c) differs little from that of the male, but the angles of the segments are less salient. Length 3-4 ram ; breadth 1. 5 mra . Color "pale yellowish or waxen." Dr. Stimpson was " inclined to consider" this form as the female of Praniza cerina. The larval forms bear a much greater resemblance to the female than to the male but are more slender than either, the thorax being, in the smaller specimens, but little broader than the pleon. The head is broad, with large prominent eyes, and is distinct from the first thoracic segment, its posterior margin being truncated. The antennulte have a short basal segment to the flagellum, which is followed by an elongate cylin- drical segment forming about half the length of the flagellum, but bearing at its end a few short segments. The mouth organs project beyond the head, giving it an acute outline, and are evidently formed for piercing and suction. The large jaws of the adult males are, of course, wanting. The maxillipeds are slender and elongated. The first pair of thoracic legs (pi. XII, fig, 78 b) are elongate, with the normal number of segments, a triangular carpus, and a strong curved dactylus, reminding one of the legs of the Cymothoidce. The first tho- racic segment is small and short and well separated from the following segments. The next two segments are quite distinct in all the forms, but usually the fourth, fifth, and sixth segments are united much as iu the adult female. These forms appear to be the young females, and were described by Dr. Stimpson under the name of Praniza cerina, / more rarely, however, specimens are found in which all the thoracic segments are distinct and somewhat resemble those of the adult male, but with their peculiarities less marked (pi. XII, fig. 79). The pleon resembles that of the adults, but is not suddenly much narrower than the thorax. The pleopods as well as the uropods are ciliated at the tip (pi. XII, fig. 78 d). Both these forms of young were taken from the body of a sculpin in the Bay of Fuudy in 1872, and, when fresh, their bodies were bright red. In alcohol they fade to a waxy yellow. Adult males of this species greatly resemble Anceus elongatus Kroyer, MARINE ISOPODA OF NEW ENGLAND, ETC. 413 but bis Pranisa Reinhardi differs in its proportions of the antennary segments from G. cerina. This species was described by Dr. Stimpson from females " dredged on gravelly and coralline bottoms in 20-30 fathoms in the Hake Bay," and males " dredged on a sandy bottom in 10 fathoms off Cheney's Head," Grand Menan, in the Bay of Fundy. It has been collected by the U. S. Fish Commission in Massachusetts Bay !, off Salem, 22-50 fathoms, gravel and soft mud ; Gulf of Maine !, at several localities ; Casco Bay !, 50 fathoms ; Bay of Fundy !, in many localities, 10 to 60 fathoms, rocks, stones, and mud, and young specimens have been taken adhering to codfish and the sculpin. It was dredged by Mr. J. F. Whiteaves in the Gulf of St. Lawrence!, in 220 fathoms, mud. Further details in regard to localities are given in the subjoined table. Specimens examined. Number. Locality. g a 1 Bottom. When col- lected. Received from Speci- mens. Dry. Ale. No. Sex. 2108 2109 2121 2110 2107 2111 2112 2113 2115 2117 2114 2116 2118 2119 2122 2120 Massachusetts Bay, 3 miles S. E. Nahant. Massachusetts Bay, off Salem E. S. E. 9 to 11 miles. Massachusetts Bar, off Salem E. S. E. 8 to 9 miles. Massachusetts Bay, off Salem E. S. E. 6 to 7 miles. Massachusetts Bay, off Salem E. S. E. 11 to 13 miles. Gulf of Maine, S. E. i S. from Cape Ann, 6 to 7 miles. Gulf of Maine be- tween Cape Ann and Isle of Shoals. Casco Bay 22 33 25-26 45-50 54-60 27-36 50 Mud Ang. 31, 1879 ,1877 ,1877 ,1877 ,1877 ,1878 ,1874 Aug. 6,1873 ,1873 ,1873 ,1872 ,1872 ,1868 ,1872 ,1872 ,1872 ,1872 1870-'72 ,1878 J. H. Emerton. U.S. Fish Com. ....do do ....do.... do ....do . do 3 3 1 1 12 12 1 2 1 10 3 3 3 12 5 5 6 00 4 1 ? Ale. Ale, Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Ale. Gravel, atones. Mud ? ? rf? cf?y. ? f 9 ...... y "*" i ! , It < g . g "9 r -S * "* n eS 2 o^< o g ^rfij 035 ! t^ ti SS^o"sT | S | ^| s 2flg 00 DD Q B 03 O ^5 w CD "t^ ^a ^j^ ^^ v c3 rt o t^" & * * ffl fl ifJrfcLo 02 OQ GO en oo oi rt c3 o$ y$ cS ci cS c3 c3 C s ++ + i !+!!!! TIBOOO OHOjy -H- : + + II I t I f ptreiii99J) +++ + + i ++: Mopn-iq^ : :+ : : : : : : :-f eou9^TgjojTn : : : ~ -t - in 4 BUOOg 'BAOJJ ^pmij jo ^Bg _ _ .ug OOSCQ _ - Qnt'Bjf jo j|nj) : _ ; ^ a < 19 OBqo NK K *^^?tr pof") oduf) - - : *ptmOQ T>TB^9TIt A ; : : : : : ; _ "punog puB^sj Suo^ : : . ; "^9SJt9J^ MQ^ + + : :- :- euctt^oj'BQ oqx TJPUOTJT - + i i i i i : *TIlo[9p Q.891'B9J-) So ..o _3 Sg rH ^H r** CO o ooco _oooo !o O C1OJO BNi-(rH-a>| 0) iH 1 nBtop^j C^ ^^ O OO ' ' I . CO [__ a ' g SS^S**- Ja '? I L, ^M 3 S HP o fl w p p g to *S w l"aE*l| " g Jo ^.^=5 o S U^p^ H PQ h 1 4|f .. i!-jtjl! 1 1: i I |H s | , fi rf| ! a 11! s 1 1 | I Slff S S 28 P 434 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 1 ft, a 5 ,- . o < l o pq I egg 89181 + A'pTmj jo jo jpi) A^a pOQ punog piraog [ S c P, W W inf eli THOID^ |.93 ii e IS |g s - -^ CJ O bfl Ca{ity ^^^which it is used. The depthTa^ given L E : : : i i i i ; :::::: : + - LLUJ :::; - MM+; ...... . : : :- :- : : : . : mot 3- 3 THl-lOO O 00 o o o C-4 TH oooo ooo Para n th ura brachiata . . Ptilanthura tenuis GNATHIID.E : Gnathia cerina TANAUXE : I 1 i Tanais vittatus Leptochelia algicola . limicola . rapax 6 ... fllum cosca 436 REPORT OF COMMISSIONER OF FISH AND FISHERIES. LIST OF AUTHORITIES. The present list includes only such works and articles, relating wholly or in part to Crustacea, as have been quoted, or otherwise used, in the preparation of the preceding paper, and is chiefly intended to aid in consultation of the authorities quoted. A few of the titles are necessa- rily given at second hand, as indicated by quotation marks in the list. The references to these works occurring throughout the article are also inclosed in quotation marks, usually with an accompanying mention of the author from whom they are taken. In all other cases the references have been made directly from the works quoted. A considerable num- ber of authorities have not been referred to, and are omitted from the list, because at present inaccessible, and, for many of the most import- ant works that 1 have been able to consult, I am indebted to the liber- ality of Professor S. I. Smith, who has given me the free use of his library and afforded other material aid in the preparation of the article. I have also had free access to the libraries of Professors Verrill, Marsh and Dana. In this list, as throughout the article, the number of the series of various scientific publications is indicated by Roman numerals in cap- itals. As far as possible references have been made to the original paging, sometimes with that of the separata added in a parenthesis, and, in the following list, a parenthesis is used to denote that the paging is, or is supposed to be, that of the separata. Agassiz, Alexander. Letter to C. P. Patterson, Superintendent Coast Survey, on the dredging operations of the U. S. Coast Survey steamer " Blake " during parts of January and February 1878. <^ Bulletin of the Museum of Comparative Zoology, vol. v, pp. 1-9. Cambridge, 1878. Andrews, A. [Limnoriaterebraus attacking telegraph cable. ] <^ Quarterly Journal of Microscopical Science, II, vol. xv, p. 332. London, 1875. Audouin, Jean Victor, and Edwards, Henri Milne. "Re'sume" d'Entornologie, ou d'Histoire naturelle des aniinaux articule~s, comp!6t6 par une iconographie de 48 planches. [2vols.] Paris, 1828-29." Audouin, Jean Victor, and Edwards, Henri Milne. Pr6cis d'Entomologie ou d'His- toire naturelle des anirnaux articule"s. Premiere division, Histoire naturelle des anne"lides, crustace"s, arachnides et myriapodes,' comple"t6 par une iconographie. [8vo, 70 pages, 48 plates.] Paris, 1829. Audouin, Jean Victor. Description de I'figypte ou recueil des observations, et des recherches qui out e"t6 faites en figypte pendant 1'expedition de l'arme"e Francaise. Explication sommaire des planches de crustace"s de 1'figypte et de la Syrie. Pub- lie"es par J. C. Savigny. Histoire naturelle, tome i, pt. 4, pp. 77-98. Paris, " 1830." Bate, C. Spence. On the British Edriophthalma. < Report of the British Associa- tion for the Advancement of Science, 1855, Reports on the state of science, pp. 18-62, pi. xii-xxii. London, 1856. Bate, C. Spence. On Praniza and Anceus and their affinity to each other. < An- nals and Magazine of Natural History, III, vol. ii, pp. 165-172, pi. vi-vii. Lon- don, Sept., 1858. Bate, C. Spence. Crustacea. [In] List of the British marine invertebrate fauna. By Robert McAndrew. <^ Report of the British Association for the Advancement of Science, 1860, Reports on state of science, pp. 217-236. London, 1861. MARINE ISOPODA OF NEW ENGLAND, ETC. 437 Bate, C. Spence. Carcinological gleanings, No. ii. <^ Annals and Magazine of Na- tural History, III, vol. xvii, pp. 24-31, pi. ii. London, 1866. Bate, C. Spence, and Westwood, John Obadiah. A History of the British sessile- eyed Crustacea. [2 vols. 8vo. ] London, 1861-1868. Beueden. See Van Beneden. Bos, Jan Ritzema. Bijdrage tot de kenuis van de Crustacea hedriophthalmata van Nederland en zijne Kusten. [8vo., 100 pages, 2 plates.] Groningen, 1874. Bosc, Louis Augustin Guillaume. Histoire naturelle des Crustace"s, contenant leur description et leurs nuBrs; avec figures dessine'es d'apres nature. [12nio., vol. ii, 296 pages, 18 plates.] Paris, An x (1802). Buchholz. Reinhold. Zweite Deutsche Nordpolfahrt "in den Jahren 1869 und 1870, unter Fiihrung des Kapitiiu Koldewey." B. ii, Part viii, Crustaceen, pp. 262-399. pi. i-xv. Leipzig, 1874. Buchholz, Reinhold. Mittheilungen naturwiss. Vereins v. Neu-Vorpom. u Rugen, i, pp. 1-40. See Milliter, Julius. Bullar, John Follett. The generative organs of the parasitic Isopoda. <^ Journal of Anatomy and Physiology, vol. xi, pp. 118-123, pi. iv. London and Camhridge, 1876. Bullar, John Follett. Herrnaphroditism among the parasitic Isopoda ; reply to Mr. Moseley's remarks on the generative organs of the parasitic Isopoda. <^ Annals and Magazine of Natural History, IV, vol. xix, pp. 254-256. London, 1877. Catta, J. D. Note sur quelques Crustace~3 erratiques. <[ Annales des Sciences natur- elles, Zoologie, VI, tome iii, pp. 1-33, pi. i-ii. Paris, 1876. Coldstream, John. On the structure and habits of the Limnoria terehrans, a minute crustaceous animal destructive to marine wooden erections, as piers, etc. < Edin- burgh New Philosophical Journal, vol. xvi, pp. 316-334, pi. vi, 1834. Cornalia, Emilio, and Panceri, Paolo. Osservazioni zoologico ed anatomische sopra uu uuovo genre di Isopodi sedentari (Gyge branchialis). <^ Memorie della Reale Accadernia delle Scienze di Torino, II, torn, xix, pp. 85-118, pi i-ii. Turin, 186L Cuvier, Georges. Le Regue Animal. See Edwards, Henri Milne, and Latreille, Pierre Andre. Czerniavski, Voldemar. Materialia ad Zoographiam Ponticam comparatam. "Transactions of the first meeting of Russian Naturalists at St. Petersburg, 1868." pp. 19-136, pi. i-viii. "1870." Dalyell, John Graham. The Powers of the Creator displayed in the Creation. [3 vols. , 4to, 145 plates. ] London, 1851-1858. Dana, James Dwight. Conspectus Crustaceorum, &c. Conspectus of the Crustacea of the Exploring Expedition * continued. Crustacea Isopoda. < American Journal of Science and Arts, II, vol. viii, pp. 424-428. New Haven, 1849. Dana, James Dwight. On the classification of the Crustacea choristopoda or tetra- decapoda. < American Journal of Science and Arts, II, vol. xiv, pp. 297-316. New Haven, 1852. Dana, James Dwight. Report on the Crustacea of the United States Exploring Ex- pedition, under the command of Charles Wilkes, U. S. N., 1838-42. Washington, Text [4to, two parts, 1618 pages], 1853. Atlas [folio, 96 plates], 1855. Dekay, James E. Zoology of New York or the New York Fauna. Part iv, Crus- tacea. [4to, 70 pages, 13 plates.] Albany, 1844. 438 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. Desmarest, Ansleme G-aetan. Malacostrace"s. < Dictionnaire des Sciences natnr- elles, tome xxviii, pp. 138-425 [56 plates]. Paris, 1823. Desmarest, Ansleme Gaetan. Considerations ge"ue~rales sur la classe des Crustacea. [8vo, 446 pages, 56 plates. ] Paris, 1825. Dohrii, Anton. Untersuchungen tiber Ban und Eutwicklnng der Arthropoden. 4. Entwicklung und Organisation von Praniza (Ancens) maxillaris. < Zeit- schrift fiir wissenschaftliche Zoologie, Band xx, pp. 55-80, taf. vi-viii. 5. Zur Kentniss des Banes von Paranthura Costana. <^Tom. cit. pp. 81-93, taf. ix. Leipzig, 1870. 7. Zur Kentniss voin Bau und der Eutwicklung von Tanais. < Jenaische Zeitschrift fiir Medicin und Naturwissenschaft, Band v, pp. 293-306, taf. xi-xii. Leipzig, 1870. Duvernoy, George Louis. Sur un nouveau genre de Pordre des Crustace"s Isopodes et sur 1'espece type de ce genre, le Ke"pone type. < Annales des Sciences natu- relles, Zoologie, II, tome xv, pp. 110-122, pi. iv B. Paris, 1841. Duvernoy, George Louis, and Lereboullet, Auguste. Essai d'une monographic des organes de la respiration de 1'ordre des Crustace"s Isopodes. <[ Annales des Sciences naturelles, Zoologie, II, tome xv, pp. 177-240, pi. vi. Paris, 1841. Ebner, Victor von. Helleria, eine neue Isopoden-Gattung aus der Familie der Oniscoiden. <^ Verhandlungen k. k. zoologisch-botanischen Gesellscliaft, Wien, Band xviii, pp. 95-114, pi. i. Vienna, 1868. Edwards, Alphonse Milne. Sur un Isopode gigantesque des grandes profondeurs de la mer. <^Comptes Rendus, tome Ixxxviii, pp. 21-23. Paris, 1879. Translated in the Aunals and Magazine of Natural History, V, vol. iii, pp. 241- 243. London, 1879. Edwards, Henri Milne. "Resume" d'Entomologie" and Precis d'Entomologie. See Audouin, Jean Victor. Edwards, Henri Milne. Annotations in Histoire naturelle des animaux sans ver- tebres, par J. B. P. A. de Lamarck, 2 me Edit., tome v, 8vo. Paris, 1838. Edwards, Henri Milne. Histoire naturelle des Crustace's, comprenant 1'anatomie, la physiologic et la classification de ces animaux. [8vo, 3 vols. text, 1 vol. plates.] Paris, tome i, 1834, tome ii, 1837, tome iii, 1840. . Published as a part of the Suites a Buifon. Edwards, Henri Milne. Le Regne Animal distribue" d'apres son organisation, par Georges Cuvier. Les Crustace's avec une atlas. [Crochard edition, text 4to, 278 pages, atlas with 87 plates.] Paris, "1849." Edwards, Henri Milne. Observations sur le squelette te"gumentaire des Crustac6s De~capodes et sur la Morphologie de ces Auimaux. <^ Auuales des Sciences natur- elles, Zoologie, III, tome xvi, pp. 221-291, pi. viii-xi. Paris, 1851. Edwards, Henri Milne. Rapport sur un travail de M. Hesse relatif aux metamor- phoses des Ance~es et des Caliges. <^ Annales des Sciences naturelles, Zoologie, IV, tome ix, pp. 89-92. Paris, 1858. Eichwald, Eduard von. "Faunae Caspio-Caucasiae illustrationes universae. < Noveaux Me"moires de la Soci6t6 Irnp6riale des Naturalistes de Moscou, vol. vii. Moscow, 1842." Pabricius, Johann Christian. Entomologia Systematica emendata et aucta secun- duni classes, ordines, genera, species, adjectis synonimis, locis, observationibus, descriptionibus. [8vo, 4 vols., vols. i and iii in two parts], Hafniae (Copenhagen) 1792-1794. Index alphabeticus. [175 pages]. 1796. MARINE ISOPODA OF NEW ENGLAND, ETC. 439 Pabricius, Johann Christian. Supplementum Entomologiae Systematicae. [8vo, 572 pages.] Hafniae (Copenhagen) 1798. Index alphabeticus. [53 pages.] 1799. Fabricius, Otho. Fauna Groenlandica. [8vo, 450 pages, 1 plate. ] Copenhagen, 1780. Fleming, John. Crustacea. <[ Encyclopaedia Britannica, 7th edition, vol. vii, pp. 497-504, pi. clxxx-clxxxi, 4to. Edinburgh (1842). Fraisse, Paul. Die Gattung Cryptoniscus Fr. Mu'ller (Liriope Rathke). e diameters : natural size indicated by cross at the right. 3, Actoniscus ellipticus Harger (p. 309) ; dorsal view, enlarged ten diame- ters; natural size indicated by line at the right. 4. Jsera albifrons Leach (p. 315) ; female : dorsal view, enlarged about ten diameters, 5. The same ; maoffiped from the left side, exterior view, enlarged twe^rv- five diameters : P, palpus : J, external lamella. 6. The same ; ma-ring*, enlarged twenty-five diameters ; a, outer, or second, pair of TnaTTTlg>; 6, inner, or first, pair of maxillae; t, inner, , outer lobe, 7. The same ; inferior surface of the pleon of a female, 8. The same ; inferior surface of the pleon of a male, (ATI the figures were drawn from nature by O. Harger. ) PLATE II. FlGt"RE 9. Janira alta Harger (p. 321) ; dorsal view, enlarged five diame: : - : natural size indicated by line at the right. 10. Janira spinosa Harger (p. 323): dorsal view of female, enlarged sir diameters. 11. Mnnnopsis typica M. Sars (p. 330) : dorsal view of male, enlarged about two diameters; 6, maxillipeds; m. basal segment; 7, external lame 2 and 3, second and third segments of palpus of maxLUipeds : c. o~ maxillse : d, inner Tna-riTlap e, one of the second pair of legs of the m /, one of the natatory legs: g. abdominal operculum of the fe^ external view. (Figures 9 and 10 were drawn from nature by O. Harger : figure 11 is copied from iL Sars, drawn by G. O. Sars.) PLATE III. FIGUEE 12. Janira alta (p. 321): a. maxiEiped; P, palpus of maxflliped : I, external lamella; 6. mandible: P. palpus of mandible: d, dentigerous lame. , molar process, enlarged twenty-five diameters. 13. The same : inferior surface of the pleon, a in the female, & in the r- enlarged ten diameters; a. single opercular plate in the fern; 6. external ; c. median plate of opeTculTnn of male. 14. Munna Fabricii Kxoyer (p. 323); female; dorsal view, enlarged about twenty diameters : natural size indicated by line at the right. 15. Eurycope robust a Harger (p. 332) ; female ; dorsal view, enlarged six diameters : natural size indicated by line at the right ; a. antenaula, enlarged twenty diameters : 6. maxiHiped : e, mandible ; d, one of the first pair of legs, each enlarged twenty diameters : , one of the first pair of legs, magnified twelve diameters; c, uropod from the left side, inner view, showing the two rami articulated near the tip. 19. The same ; pleopods of second pair from the right side, anterior views, enlarged ten diameters; a, common form in males; 6, rarer form in male ; s, elongated stylet, articulated near the base of the inner lamella; c, form in the female. 20. Chiridotea Tuftsii Harger (p. 340); female; dorsal view, enlarged five diameters ; natural size indicated by the line at the right. 21. The same ; left maxilliped, enlarged twenty-five diameters ; e, external lamella; m, basal segment;- 1, 2, 3, segments of palpus. 22. The same ; pleopod of the second pair, from a male, enlarged twenty diameters ; s, elongated stylet, articulated near the base of the inner lamella. (All the figures were drawn from nature by O. Harger.) PLATE V. FIGURE 23. Chiridotea Tuftsii Harger (p. 340); a, antennula; 6, antenna; c, leg of the first pair ; d, leg of the fourth pair ; all enlarged twelve diameters ; e, left uropod, or opercular valve, inner view, enlarged ten diameters. 24. Idotea irrorata Edwards (p. 343); dorsal view, enlarged two diameters; natural size shown by the line on the left. 25. The same ; a, antennula ; 6, antenna ; c, left uropod or opercular valve, external view ; all enlarged six diameters. 26. The eamo ; a, right maxilliped, enlarged twelve diameters, I, external lamella ; m, basal segment ; 1, 2, 3, 4, segments of palpus of maxilliped ; b, pleopod of the second pair from a male, enlarged eight diameters, show- ing stylet, s, articulated near the base of the inner lamella. 27. Idotea phosphorea Harger (p. 347); dorsal view, enlarged about two diameters ; natural size shown by the line on the right. 28. The same ; a, antenna, enlarged six diameters ; &, maxilliped, enlarged twelve diameters, showing, I, external lamella ; m, basal segments ; 1, 2, 3, 4, segments of the palpus of maxilliped ; c, leg of the first pair ; d, leg of the second pair, both enlarged six diameters ; e, right uropod, or opercular valve, inner view, enlarged six diameters. 29. The same ; pleopod of the second pair from a male, enlarged eight diam- eters ; s, stylet articulated near the base of the inner lamella ; ', distal end of stylet reversed and enlarged thirty diameters. (Figure 24 was drawn by Mr. J. H. Emerton, the others by O. Harger.) PLATE VI. FIGURE 30. Idotea robusta Kroyer (p. 349) ; dorsal view, enlarged two diameters ; natural size shown by the line at the right. 31. The same; a, antenna; &, leg of th<> first pair, each enlarged six diam- i eters : c, left uropod, or opercular valve, inner view, enlarged four diameters. EXPLANATION OF THE PLATES. 455 FIGURE 32. The same ; a, maxilliped, enlarged twelve diameters ; I, external lamella ; 1, 2, 3, 4, segments of palpus; &, maxilla of the outer or second pair; c, pleopod of the second pair from a male, enlarged six diameters ; , stylet articulated near the base of the inner lamella. 33. Synidotea nodulosa Harger (p. 351) ; dorsal view, enlarged four diam- eters ; natural size indicated by the line at the right. 34. The same ; a, antennula ; /, flagellar segment ; 6, antenna ; c, leg of the first pair from the right side ; d, right uropod, or opercular valve, all enlarged ten diameters. 35. The same; a, maxilliped from the right side, showing, I, external lamella ; m, basal segment ; 1, 2, 3, segments of palpus, enlarged twenty diameters ; Z>, maxilla of the outer or second pair ; c, maxilla of the inner or first pair, both enlarged twenty diameters ; d, pleopod of the second pair from a male, enlarged twelve diameters ; s, stylet articulated near the base of the inner lamella. 36. Erichsonia attenuata Harger (p. 356) ; dorsal view, enlarged three diam- eters, natural size indicated by the line at the right. (Figures 30 and 36 were drawn by Mr. J. H. Emerton, the others by O. Harger. ) PLATE VII. FIGURE 37. Erichsonia attenuata Harger (p. 356) ; a, antennula ; 6, antenna, each enlarged twelve diameters ; c, maxilliped, showing, I, external lamella, enlarged thirty diameters ; d, uropod, or opercular valve, enlarged twelve diameters ; e, pleopod of the second pair from a male, enlarged fifteen diameters; s, stylet, articulated near the base of the inner la- mella ; s', distal end of stylet, enlarged fifty diameters. 38. Erichsonia filiformis Harger (p. 355); dorsal view, enlarged five diam- eters, natural size indicated by the line at the right. 39. The same ; a, antennula ; "b, antenna ; c, leg of the first pair; d, uropod, or opercular valve, each enlarged twelve diameters. 40. The same ; a, maxilla of outer or second pair ; ft, maxilla of inner or first pair ; c, mandible, showing molar process, m, and dentigerous lamella, d, all enlarged thirty diameters. 41. The same ; a, maxilliped, showing, I, external lamella; m, basal segment, and 1, 2, 3, 4, segments of palpus, enlarged thirty diameters ; J>, pleopod of the second pair from a male, enlarged fifteen diameters ; s, stylet, ar- ticulated near the base of the inner lamella ; s', distal end of stylet, enlarged fifty diameters. 42. Epelys trilobus Smith (p. 358) ; dorsal view, enlarged ten diameters : natural size indicated by the line at the right. 43. The same; a, maxilliped from the left side, enlarged twenty diameters; I, external lamella ; m, basal segment ; 1, 2, 3, segments of palpus of maxilliped ; &, pleopod of second pair from a male, enlarged twenty diameters; s, stylet, articulated near the base of the inner lamella; s', end of stylet, enlarged fifty diameters. (All the figures were drawn from nature by O. Harger.) PLATE VIII. FIGURE 44. Epelys montosus Harger (p. 359) ; dorsal view, enlarged six diameters, natural size indicated by the line at the right. 45. The same; a, antennula; /, flagellar segment; 6, antenna; c, maxilliped from the left side; I, external lamella; m, basal segment; 1,2,3, seg- ments of palpus ; all the figures enlarged twenty diameters. 46. The same; a, leg of the first pair, enlarged twenty diameters; 6, right uropod or opercular valve, enlarged fifteen diameters. 456 REPORT OF COMMISSIONER OF FISH AND FISHERIES. FIGURE 47. The same; pleopod of the second pair, from a male, enlarged twenty di- ameters ; s, stylet, articulated near the base of the inner lamella ; *, distal end of stylet, enlarged sixty-six diameters. 48. Astacilla grauulata Harger (p. 364); female; dorsal view, enlarged four diameters, natural size indicated by the line at the right ; a, antennula of male ; b, fourth thoracic segment of male ; c, inferior surface of pleon of a male, showing opercular valves; all the figures enlarged four diameters. 49. The same ; a, flagellum of antenna, enlarged twenty diameters ; a', por- tion of inner margin of the same, enlarged one hundred diameters ; b, one of the first pair of legs, upper surface, enlarged twenty diameters. 50. The same ; one of the fourth pair of legs, enlarged twenty diameters. 51. The same ; inner surface of left opercular plate, or uropod, from a female, enlarged twenty diameters. (All the figures were drawn from nature by O. Harger. ) PLATE IX. FIGURE 52. Astacilla grauulata Harger (p. 364); a, maxilliped; m, basal segment; I, external lamella ; b, outer maxilla ; c, inner maxilla ; all enlarged twenty diameters. 53. Sphserorna quadridentatum Say (p. 368); dorsal view, enlarged five diameters; natural size indicated by the line at the right. 54. The same ; a, antennula ; b, antenna ; c, pleopod of the second pair, from a male, showing stylet, s, articulated near the base of the inner lamella; all the figures enlarged ten diameters. 55. Li'mnoria lignorum White (p. 373) ; dorsal view, enlarged ten diameters ; natural size indicated by the line at the right. 56. The same ; a, antennula ; b, antenna ; c, maxilliped ; d, maxilla of the outer or second pair ; e, maxilla of the inner or first pair ; /, mandible, all enlarged twenty-five diameters ; e', distal end of outer lobe of first pair of maxilla}, enlarged sixty-six diameters. 57.-^-The same ; a, last segment of pleon, with attached uropods ; dorsal view, enlarged ten diameters; b, uropod with dotted adjacent outline of last segment of pleon, enlarged thirty diameters ; c, first pair of pleopods ; d, pleopod of the second pair, from a male, showing stylet, , articu- lated to the inner lamella ; both figures enlarged twenty diameters. 58. Cirolana concharum Harger, (p. 378) ; lateral view, enlarged about three diameters. (Figure 53 was drawn by Mr. J. H. Emerton, 55 by Prof. S. I. Smith, 58 by Mr. J. H. Blake, and the others by O. Harger. ) PLATE X. FIGURE 59. Cirolana concharum Harger (p. 378) ; dorsal view, enlarged about three diameters. The natural size is shown by the line at the right. 60. The same ; antennula, enlarged ten diameters. 61. The same; a, antenna enlarged ten diameters; b, maxilla of the outer or second pair; c, maxilla of the inner or first pair; d, mandible from the right side, inner view ; p, palpus ; m, molar area ; the last three figures enlarged five diameters. 62. The same ; a, maxilliped from the right side, exterior view, showing, I, external lamella; m, basal segment; 1, 2, 3, 4, 5, segments of the palpus; b, leg of the fourth pair ; both the figures enlarged five diameters. 63. The same ; uropod from the right side ; inferior view, enlarged five di- ameters. 64. JEga psora Kroyer (p. 384) ; a, dorsal and b ventral views of a young indi- vidual. The central line indicates the length of > the specimen, natural EXPLANATION OF THE PLATES. 457 ^ which is here enlarged three diameters. Adults attain about the size of the figure. FIGURE 65. Nerocila munda Harger (p. 392) ; dorsal view of the type specimen, en- larged about four diameters. The natural size is shown by the cross on the right ; a, uropod, enlarged six diameters. 66. JSgathoa loliginea Harger (p. 393) ; type specimen ; a, dorsal, and I, ven- tral view, enlarged four diameters. Its natural size is shown by the line between the figures. (Figure 59 was drawn by Mr. J. H. Blake, the others by O. Harger.) PLATE XL FIGURE 67. Livoneca ovalis White (p. 395) ; a, antennula ; 6, antenna ; c, mandibular palpus; each enlarged twenty diameters; d, one of the first pair of legs; e, one of the seventh pair of legs ; /, uropod ; each enlarged ten diam- eters. 68. Anthura polita Stimpson (p. 398) ; dorsal view, enlarged four diameters. The natural size is shown by the line at the right; a, antennula; &, antenna, each enlarged ten diameters; c, leg of the first pair; d, leg of the third pair ; e, right pleopod of the first pair, interior view, showing inner ramus without cilia; /, pleopod of the second pair from a male, showing stylet articulated to inner lamella ; each of the figures c to/ enlarged eight diameters ; g, lateral view of pleon, enlarged six diam- eters. 69. The same; a, maxilliped, enlarged twenty diameters; 6, maxilla, enlarged twenty-five diameters; V, distal end of the same, enlarged sixty diam- eters. 70. Paranthura brachiata Harger (p. 402) ; dorsal view, enlarged about three diameters ; natural size shown by the line at the right ; a, antennula ; &, antenna, enlarged eight diameters ; c, right maxilliped, enlarged six- teen diameters ; d, maxilla, enlarged sixteen diameters ; d', distal end of the same, enlarged fifty diameters ; e, leg of the first pair ; /, first pleopod from the right side, inner view, showing ciliated inner lamella ; g, pleopod of the second pair from a male, showing stylet articulated to the inner lamella ; figures e to g enlarged eight diameters. 71. Ptilanthura tennis Harger (p. 406); male; dorsal view, enlarged about four diameters ; a, inferior view of the head and first thoracic segment, enlarged eight diameters ; the flagellum of the antennula? omitted ; &, maxilliped ; c, maxilla, each enlarged fifty diameters ; d, first right ple- opod, seen from within, showing ciliated inner lamella ; e, second left pleopod, showing stylet s articulated to the inner lamella in the males. 72. The same ; one of the first pair of legs of a male, enlarged sixteen diam- eters. 73. The same; female ; dorsal view of the head, enlarged twenty- five diam- eters. (Figure 71, excepting "b-d, was drawn by Mr. J. H. Emerton, the others by O. Harger.) PLATE XII. FIGURE 74. Ptilanthura tenuis Harger (p. 406); a, antennula; 6, antenna; each enlarged twenty diameters, from a male. 75. Gnathia cerina Harger (p. 410) ; male ; dorsal view, enlarged ten diame- ters. 76. The same ; a, antennula ; 6, antenna, each enlarged thirty-eight diame- ters; c, mandibles (I, left, r, right), enlarged thirty-eight diameters; d, first leg or first gnathopod from the right side, enlarged twenty-five diameters; all the figures from the male sex. 77. The same (p. 411); female; dorsal view, enlarged. ten diameters. 458 KEPORT OF COMMISSIONER OF FISH AND FISHERIES. FIGURE 78. The same ; a, one of the first pair of legs or first gnathopod of a female, enlarged thirty-eight diameters; &, one of the first pair of legs in a young, parasitic individual, enlarged sixty diameters; c, pleon, with the last and part of the penultimate thoracic segments of a female, dorsal view, enlarged twenty diameters ; d, pleopod of a young, pari- sitic individual, enlarged sixty diameters ; e, pleopod of an adult male, enlarged sixty diameters. 79. The same ; young male ; dorsal view, enlarged twenty diameters. 80. Leptochelia algicola Harger (p. 421); male; lateral view, enlarged twenty diameters ; natural size indicated by the line above. (All the figures were drawn from nature by O. Harger. ) PLATE XIII. FIGURE 81. Tauais vittatus Lilljeborg (p. 418); dorsal view, enlarged eight diame- ters. The transverse bands of hairs on the pleon are not sufficiently distinct. 82. The same ; one of the first pair of pleopods, enlarged thirty diameters. 83. Leptochelia algicola Harger (p. 421) ; female ; dorsal view, enlarged twenty diameters ; natural size indicated by the line at the right. 84. The same ; c,, antennula ; l>, one of the first pair of legs ; both from a female specimen and enlarged twenty-five diameters. 85. The same; hand, or propodus and dactylus of the first pair of legs, enlarged forty-eight diameters, showing the comb of setse on the pro- podus. 86. The same ; uropods of a male, enlarged seventy diameters ; &, basal seg- ment; t, inner six-jointed ramus; o, outer ramus. 87. Leptochelia limicola Harger (p. 424) ; female ; dorsal view, enlarged twenty diameters ; natural size shown by the line at the right. 88. The same; a, antennula; b, antenna; c, leg of the first pair; d, leg of the second pair; all from the female sex and enlarged twenty-five diameters. 89. Leptochelia rapax Harger (p. 424); male; dorsal view, enlarged about twelve diameters. 90. The same; hand, or propodus and dactylus of male, enlarged sixteen diameters. 91. Leptochelia coeca Harger (p. 427); type specimen, female; a, antennula; Z>, leg of the first pair ; c, uropod ; each enlarged fifty diameters. (All the figures were drawn from nature by 0. Harger.) PLATE I. FIGURE 1. PMloscia vittata Say (p. 306); dorsal view, enlarged sis diameters; natural size indicated by cross at the right. 2. Scyphacella arenicola Smith (p. 307) ; dorsal view, enlarged about twelve diameters; natural size indicated by cross at the right. 3. Actoniscus ellipticus Harger (p. 309) ; dorsal view, enlarged ten diame- ters; natural size indicated by line at the right. 4. Jgera albifrons Leach (p. 315) ; female ; dorsal view, enlarged about ten diameters. 5. The same ; maxilliped from the left side, exterior view, enlarged twenty- five diameters ; P, palpus ; I, external lamella. 6. The same ; maxillae, enlarged twenty-five diameters ; a, outer, or second, pair of maxillse; &, inner, or first, pair of maxillae; i, inner, e, outer lobe. 7. The same ; inferior surface of the pleon of a female. 8. The same ; inferior surface of the pleon of a male. (All the figures were drawn from nature by O. Harger.) Report IT. S. F. C. 1878. Harger. Marine Isopods. Plate I. Fig. 1. Fig. 3. JNb.934. No.9.11. PLATE II. FIGURE 9. Janira alta Harger (p. 321); dorsal view, enlarged five diameters; natural oize indicated by line at the right. 10. Janira spinosa Harger (p. 323); dorsal view of female, enlarged six diameters. 11. Munnopsis typica M. Sars (p. 330) ; dorsal view of male, enlarged about two diameters; b, maxillipeds; m, basal segment; I, external lamella; 2 and 3, second and third segments of palpus of maxillipeds ; c, outer maxillae ; d, inner maxillae ; e, one of the second pair of legs of the male ; /, one of the natatory legs; g, abdominal operculum of the female, external view. (Figures 9 and 10 were drawn from nature by O. Harger ; figure 11 is copied from M. Sars, drawn by G. O. Sars.) Keport U. S. F. C. 1878. Harger. Marine Isopods Plate II. Fig. 10. Fig 9- lfo.924. Fig. 11. "No. 490 ^rv v - . . - V, Urg. *-,. , f . I PLATE III. FiGURB 12. Janira alta (p. 321); a, maxilliped ; f, palpus of maxilliped; ?, external lamella ; 6, mandible ; P, palpus of mandible ; d, dentigerous lamella ; TO, molar process, enlarged twenty-five diameters. 13. The same ; inferior surface of the pleon, a in the female, & in the male, enlarged ten diameters; a, single opercular plate in the female; 6, external ; e, median plate of operculum of male. 14. Munna Fabricii Kroyer (p. 325); female; dorsal view, enlarged about twenty diameters ; natural size indicated by line at the right. 15. Eurycope robusta Harger (p. 332); female; dorsal view, enlarged six diameters; natural size indicated by line at the right; a, antennula, enlarged twenty diameters ; &, maxilliped ; c, mandible ; d, one of the first pair of legs, each enlarged twenty diameters; d', propodus and dactylusof the first pair of legs, enlarged about thirty-eight diameters; e, propodus and dactylus of the second pair of legs, enlarged twenty diameters; /, one of the sixth pair of legs; g, uropod, each enlarged twenty diameters. (Figure 14 was drawn from nature by Mr. J. H. Emerton, the others by O. Harger.) Keport U. S. F. C. 1878. Harger. Marine Isopods. Plate HI. Fig. 12. Fig. 14. Fig. 15. PLATE IV. FIGURE 16. Chiridotea ceeca Harger (p. 338); dorsal view, enlarged nearly four diameters ; natural size indicated by the line at the right. 17. The same ; a, antennula ; 5, antenna ; each enlarged twelve diameters. 18. The same ; a, maxilliped from the right side, external view ; I, external lamella ; m, maxilliped proper; l r 2, 3, first, second, and third segments of the palpus of the maxilliped, enlarged twenty diameters ; 6, one of the first pair of legs, magnified twelve diameters; c, uropod from the left side, inner view, showing the two rami articulated near the tip. 19. The same ; pleopods of second pair from the right side, anterior views, enlarged ten diameters ; a, common form in males ; 5, rarer form in male ; ,. elongated stylet, articulated near the base of the inner lamella ; e, form in the female. 20. Chiridotea Tuftsii Harger (p. 340); female ; dorsal view, enlarged five diameters ; natural size indicated by the line at the right. 21. The same; left maxilliped, enlarged twenty -five diameters; e, external lamella; m, basal segment; 1, 2, 3, segments of palpus. 22. The same ; pleopod of the second pair, from a male, enlarged twenty diameters; s, elongated stylet, articulated near the base of the inner lamella. (All the figures were drawn, from nature by O. Harger.) Report 17. S.F.C. 1878. Harger. Marine Isopods. Plate IV. Fig. 16. Fig. 20. So. 7S2 Fig. 19. Fig. 21. X2S Fig. 22. jf 0.950. -Fig. 17. . So.969; PLATE V. FIGUBE23. Chiridotea Tnffcsii Harger (p. 340); a, antennula; 6, antenna; c, leg of the first pair ; d, leg of the fourth pair ; all enlarged twelve diameters ; e, left uropod, or opercular valve, inner view, enlarged ten diameters. 24. Idotea irrorata Edwards (p. 343); dorsal view, enlarged two diameters; natural size shown by the line on the left. 25. The same ; a, antennula ; b, antenna ; c, left uropod or opercular valve, external view ; all enlarged six diameters. 26. The same; a, right maxilliped, enlarged twelve diameters, I, external lamella ; m, basal segment ; 1, 2, 3, 4, segments of palpus of maxilliped ; b, pleopod of the second pair from a male, enlarged eight diameters, show- ing stylet, s, articulated near the base of the inner lamella. 27. Idotea phosphorea Harger (p. 347); dorsal view, enlarged about two diameters ; natural size shown by the line on the right. 28. The same ; a, antenna, enlarged six diameters ; 6, maxilliped, enlarged twelve diameters, showing, I, external lamella ; m, basal segments; 1, 2, 3, 4, segments of the palpus of maxilliped ; c, leg of the first pair ; d, leg of the second pair, both enlarged six diameters ; e, right uropod, or opercular valve, inner view, enlarged six diameters. 29. The same ; pleopod of the second pair from a male, enlarged eight diam- eters ; s, stylet articulated near the base of the inner lamella ; ', distal end of stylet reversed and enlarged thirty diameters. (Figure 24 was drawn by Mr. J. H. Enierton, the others by 0. Harger.) Report U. S. F. C. 1878. Harger. Marine Isopods. Plate V. Fig. 25. Fig. 24. No.953. Fig. 29. Fig. 23. ^0.955. ifo.949. PLATE VI. FIGURE 30. Idotea robusta Kroyer (p. 349) ; dorsal view, enlarged two diameters ; natural size shown by the line at the right. 31. The same; a, antenna; &, leg of the first pair, each enlarged six diam- eters; c, left uropod, or opercular valve, inner view, enlarged four diameters. FIGURE 32. The same ; a, maxilliped, enlarged twelve diameters ; I, external lamella ; 1, 2, 3, 4, segments of palpus ; &, maxilla of the outer or second pair ; c, pleopod of the second pair from a male, enlarged six diameters ; a, stylet articulated near the base of the inner lamella. 33. Synidotea nodulosa Harger (p. 351) ; dorsal view, enlarged four diam- eters ; natural size indicated by the line at the right. 34. The same ; a, antennula ; /, flagellar segment ; &, antenna ; c, leg of the first pair from the right side ; d, right uropod, or opercular valve, all enlarged ten diameters. 35. The same; a, maxilliped from the right side, showing, I, external lamella ; m, basal segment ; 1, 2, 3, segments of palpus, enlarged twenty diameters ; &, maxilla of the outer or second pair ; c, maxilla of the inner or first pair, both enlarged twenty diameters ; d, pleopod of the second pair from a male, enlarged twelve diameters; s, stylet articulated near the base of the inner lamella. 36. Erichsonia attenuata Harger (p. 356) ; dorsal view, enlarged three diam- eters, natural size indicated by the line at the right. (Figures 30 and 36 were drawn by Mr. J. H. Emerton, the others by O. Harger.) Report U. S. F. C. 1878. Harger. Marine Isopods. Plate VI. Fig 31. Fit;. 33. XG :No.9J7. Fig 35. ,TTo.951. Fig. 34. 310.938. Fig. 30. o. 535 534 PLATE VII. FIGURE 37. Erichsonia attenuata Harger (p. 356) ; a, antennula ; Z>, antenna, each enlarged twelve diameters ; c, maxilliped, showing, I, external lamella, enlarged thirty diameters; d, uropod, or opercular valve, enlarged twelve diameters ; e, pleopod of the second pair from a male, enlarged fifteen diameters ; s, stylet, articulated near the base of the inner la- mella ; s', distal end of stylet, enlarged fifty diameters. 38. Erichsonia filiformis Harger (p. 355); dorsal view, enlarged five diam- eters, natural size indicated by the line at the right. 39. The same ; a, antennula ; &, antenna ; c, leg of the first pair ; d, uropod, or opercular valve, each enlarged twelve diameters. 40. The same; a, maxilla of outer or second pair; &, maxilla of inner or first pair ; c, mandible, showing molar process, m, and dentigerous lamella, d, all enlarged thirty diameters. 41. The same; a, maxilliped, showing, I, external lamella; m, basal segment, and 1, 2, 3, 4, segments of palpus, enlarged thirty diameters ; 6, pleopod of the second pair from a male, enlarged fifteen diameters ; s, stylet, ar- ticulated near the base of the inner lamella ; s', distal end of stylet, enlarged fifty diameters. 42. Epelys trilobus Smith (p. 358); dorsal view, enlarged ten diameters; natural size indicated by the line at the right. 43,-eThe same ; a, maxilliped from the left side, enlarged twenty diameters ; I, external lamella; m, basal segment; 1, 2, 3, segments of palpus of maxilliped ; &, pleopod of second pair from a male, enlarged twenty diameters; 8, stylet, articulated near the base of the inner lamella; s', end of stylet, enlarged fifty diameters. (AH the figures were drawn from nature by O. Harger.) Report tT. S. F. C. 1878. Harger. Marine Isopods. Plate VII. Fig. 40., X13- a IX 0.963. Fig. 43. ' /-% -No.942, Fig. 39. Fig. 42. Fig. 38. , 7fi3 PLATE VIII. FIGURE 44. Epelys montosus Harger (p. 359) ; dorsal view, enlarged six diameters, natural size indicated by the line at the right. 45. The same; a, antennula; /, flagellar segment; b, antenna; c, maxilliped from the left side ; I, external lamella ; m, basal segment ; 1, 2, 3, seg- ments of palpus ; all the figures enlarged twenty diameters. 46. The same ; a, leg of the first pair, enlarged twenty diameters ; &, right uropod or operoular valve, enlarged fifteen diameters. FIGURE 47. The same; pleopod of the second pair, from a male, enlarged twenty di- ameters; *, stylet, articulated near the base of the inner lamella; ', distal end of stylet, enlarged sixty-six diameters. 48. Astacilla granulata Harger (p. 364); female; dorsal view, enlarged four diameters, natural size indicated by the line at the right ; a, antennula of male ; b, fourth thoracic segment of male ; c, inferior surface of pleon of a male, showing opercular valves; all the figures enlarged four diameters. 49. The same ; a, flagellum of antenna, enlarged twenty diameters ; a', por- tion of inner margin of the same, enlarged one hundred diameters ; 6, one of the first pair of legs, upper surface, enlarged twenty diameters. 50. The same ; one of the fourth pair of legs, enlarged twenty diameters. 51. The same ; inner surface of left opercular plate, or uropod, from a female, enlarged twenty diameters. (All the figures were drawn from nature by O. Harger.) Report IT. S. F. C. 1878. Harger. Marine Isopods. Plate VIII. Fig. 44. 2*0.937. Fig. 49. Fig. 51. Fig. 46. No. 495 '7 Ko.965, No. 194 2*0.936. PLATE IX. FIGURE 52. Astacilla granulata Harger (p. 364); a, maxilliped ; m, basal segment; I, external lamella; b, outer maxilla; c, inner maxilla; all enlarged twenty diameters. 53. Sphaeroma qnadridentatum Say (p. 368); dorsal view, enlarged five diameters; natural size indicated by the line at the right. 54. The samk$ a, antennula ; b, antenna ; c, pleopod of the second pair, from a male, showing stylet, s, articulated near the base of the inner lamella; all the figures enlarged ten diameters. 55. Limnoria lignorum White (p. 373) ; dorsal view, enlarged ten diameters ; natural size indicated by the line at the right. 56. The same ; a, antennula ; b, antenna ; c, maxilliped ; d, maxilla of the outer or second pair ; c, maxilla of the inner or first pair ; /, mandible, all enlarged twenty-five diameters ; e', distal end of outer lobe of first pair of maxillas, enlarged sixty-six diameters. 57. The same ; , last segment of pleon, with attached uropods; dorsal view, enlarged ten diameters; b, uropod with dotted adjacent outline of last segment of pleon, enlarged thirty diameters ; c, first pair of pleopods ; d, pleopod of the second pair, from a male, showing stylet, 8, articu- lated to the inner lamella ; both figures enlarged twenty diameters. 58. Cirolana couchamm Harger, (p. 378) ; lateral view, enlarged about three diameters. (Figure 53 was drawn by Mr. J. H. Emerton, 55 by Prof. S. I. Smith, 58 by Mr. J. H. Blake, and the others by O. Harger. ) Report IT. S. F. C. 1878. Harger. Marine Isopods. Plate IX. Pig. 52. JJo. 492 S20 Ko.930. Fig. 56. Nb.954. Fig. 58. Fig. 53. No. 532 Fig. 54. . No.920. Fig. 55. . 531 PLATE X. FIGURE 59. Cirolana concharnm Harger (p. 378) ; dorsal view, enlarged about three diameters. The natural size is shown by the line at the right. 60. The same ; antennula, enlarged ten diameters. 61. The same; a, antenna enlarged ten diameters; I, maxilla of the outer or second pair ; c, maxilla of the inner or first pair : d, mandible from the right side, inner view ; p, palpus ; m, molar area ; the last three figures enlarged five diameters. 62. The same ; a, maxilliped from the right side, exterior view, showing, I, external lamella; m, basal segment; 1, 2, 3, 4, 5, segments of the palpus; 6, leg of the fourth pair ; both the figures enlarged five diameters. 63. The same ; uropod from the right side ; inferior view, enlarged five di- ameters. 64. -35ga psora Kroyer (p. 384) ; a, dorsal and fc ventral views of a young indi- vidual. The central line indicates the length of the specimen, natural size, which is here enlarged three diameters. Adults attain about the size of the figure. FIGURE 65. Nerocila munda Harger (p. 392); dorsal view of the type specimen, en- larged about four diameters. The natural size is shown by the cross on the right ; a, uropod, enlarged six diameters. 66. ^Egathoa loliginea Harger (p. 393) ; type specimen ; a, dorsal, and &, ven- tral view, enlarged four diameters. Its natural size is shown by the line between the figures. (Figure 59 was drawn by Mr. J. H. Blake, the others by O. Harger.) Report U. S. F. C. 1878. Harger. Marine Isopods. Plate X. Fig. 59, Fig. 60. Tig. 62. .No.903. Fig. 63. \ Fig. G.".. t Fig. C4. o 'S ^0.950. PLATE XL FIGURE 67. Livoneca ovalis White (p. 395) ; a, antennula; b, antenna; c, m.indibular palpus ; each enlarged twenty diameters ; d, one of the first pair of legs ; e, one of the seventh pair of legs ; /, uropod ; each enlarged ten diam- eters. 68. Anthura polita Stimpson (p. 398) ; dorsal view, enlarged four diameters. The natural size is shown by the line at the right; a, antennula; b, antenna, each enlarged ten diameters ; c, leg of the first pair ; d, leg of the third pair ; e, right pleopod of the first pair, interior view, showing inner ramus without cilia; /, pleopod of the second pair from a male, showing stylet articulated to inner lamella; each of the figures c to/ enlarged eight diameters ; g, lateral view of pleon, enlarged six diam- eters. 69. The same, a, maxilliped, enlarged twenty diameters; & r maxilla, enlarged twenty-five diameters ; V, distal end of the same, enlarged sixty diam- eters. 70. Paranthura brachiata Harger (p. 402) ; dorsal view, enlarged about three diameters ; natural size shown by the line at the right ; a, antennula ; b, antenna, enlarged eight diameters ; c, right maxilliped, enlarged six- teen diameters ; d, maxilla, enlarged sixteen diameters ; d', distal end of the same, enlarged fifty diameters ; e, leg of the first pair ; /, first pleopod from the right side, inner view, showing ciliated inner lamella ; <7, pleopod of the second pair from a male, showing stylet articulated to the inner lamella ; figiires e to g enlarged eight diameters. 71. Ptilanthura tennis Harger (p. 406); male; dorsal view, enlarged about four diameters ; a, inferior view of the head and first thoracic segment, enlarged eight diameters ; the fl agelluin of the antennulso omitted ; b, maxilliped ; c, maxilla, each enlarged fifty diameters ; d, first right ple- opod, seen from within, showing ciliated inner lamella; e, second left pleopod, showing stylet s articulated to the inner lamella in the males. 72. The same j one of the first pair of legs of a male, enlarged sixteen diam- eters. 73. The same; female ; dorsal view of the head, enlarged twenty- five diam- eters. (Figure 71, excepting b-d, was drawn by Mr. J. H. Emerton, the others by 0. Harger.) Report TT. S. F. C. 1878. Harger. Marine Isopods. Plate XL Fig. 68. Fig. 67. 2*0.961. No.911, PLATE XII. FIGURE 74. Ptilanthnra tennis Harger (p. 406); a, antennula; ft, antenna; each, enlarged twenty diameters, from a male. 75. Gnathia cerina Harger (p. 410) ; male ; dorsal view, enlarged ten diame- ters. 76. The same ; a, antennnla ; ft, antenna, each enlarged thirty-eight diame- ters; e, mandibles (I, left, r, right), enlarged thirty-eight diameters; d, first leg or first gnathopod from the right side, enlarged twenty-five diameters ; all the figures from the male sex. 77. The same (p. 411); female; dorsal view, enlarged ten diameters. 78. The same ; a, one of the first pair of legs or first gnathopod of a female, enlarged thirty-eight diameters ; ft, one of the first pair of legs in a young, parasitic individual, enlarged sixty diameters; c, pleon, with the last and part of the penultimate thoracic segments of a female, dorsal view, enlarged twenty diameters ; d, pleopod of a young, pari- sitic individual, enlarged sixty diameters ; e, pleopod of an adult male, enlarged sixty diameters. 79. The same ; young male ; dorsal view, enlarged twenty diameters. 80. Leptochelia algicola Harger (p. 421); male; lateral view, enlarged twenty diameters ; natural size indicated by the line above, (All the figures were drawn from nature by O. Harger.) Report IT. S. F. C. 1878. Harger. Marine Isopods. Plate XH Fig. 75. IV 79. I If 0.903. a 2*0.926. tfo.907. Fig. 80. r i .1 i JTo.909. PLATE XIII. FIGURE 81. Taiiais vittatus Lilljeborg (p. 418); dorsal view, enlarged eight diame- ters. The transverse bands of hairs on the pleon are not sufficiently distinct. 82. The same ; one of the first pair of pleopods, enlarged thirty diameters. 83. Leptochelia algicola Harger (p. 421); female; dorsal view, enlarged twenty diameters ; natural size indicated by the line at the right. 84. The same ; a, antennula ; b, one of the first pair of legs ; both from a female specimen and enlarged twenty-five diameters. 85. The same; hand, or propodus and dactylus of the first pair of legs, enlarged forty-eight diameters, showing the comb of seta? on the pro- podus. 86. The same ; uropods of a male, enlarged seventy diameters ; 6, basal seg- ment; i, inner six-jointed ramus; o, outer rarnus. 87. Leptochelia limicola Harger (p. 424) ; female ; dorsal view, enlarged twenty diameters ; natural size shown by the line at the right. 88. The same; a, antennula; 6, antenna; e, leg of the first pair; d, leg of the second pair; all from the female sex and enlarged twenty-five diameters. 89. Leptochelia rapax Ilarger (p. 424); male; dorsal view, enlarged about twelve diameters. 90. The same; hand, or propodus and dactylus of male, enlarged sixteen diameters. 91. Leptochelia coeca Harger (p. 427); type specimen, female; a, antonnula; &, leg of the first pair ; c, uropod ; each enlarged fifty diameters. (All the figures were drawn from nature by O. Ilarger.) Report U. S. F. C. 1878. Harger. Marine Isopoda. Plate XIII. Fig. 90. Kg. 86. No. 497. No.931. Fig. 83. X1G \ \ \ -* No. 496 > \ Tj Fig. 85. Kb.902. Fig. 8R. Fig. 81. 3S T o.901. Fig. 84. No. 49S. Fig. 91. No.918. . 87. Nb.953. ALPHABETICAL INDEX TO THE REPORT ON THE MARINE ISOPODA OF NEW ENGLAND AND ADJACENT WATERS. fin the following index the first reference for the names of the families, genera, and species here de- scrihed is to the page on which such description is made. The list of authorities, heing alphabetically arranged, is not indexed.] Abdomen, 298. Actaecia, 309. Actoniscus, 309, 305. ellipticus, 309, 428, 433. Mga., 383, 377, 378, 387, 431. concharum, 378. emarginata, 384. entaillee, 384, polita, 381. psora, 384, 429, 430, 434. .Egathoa, 393, 391. loliginea, 393, 428/434. .Egida), 382, 300, 303, 377, 430, 43L .ffiro-spirantia, 305. Alitropus, 391. Anceus, 409, 410. americanus, 410, 411. elongatus, 412. Ancoral legs, 300. Andrews, A, on Limnoria, 375. Anilocra, 391. mediterranea, 430. Anisocheirus, 416. Antennae, 298. Antennulae, 298. Anthura, 398, 301, 397, 431. brunnea, 398, 401. carinata, 401. gracilis, 398, 401. polita, 398, 406, 429, 434. Anthuridoe, 396, 301, 303, 361, 431. Apsendes, 304, 414, 416, 431. ArcturidzB, 361, 303, 397, 430, 431. Arcturus, 361, 363. Baffini, 362. Armadillidae, 314. Armadillo, 305. Armida bimarginata, 343. Artystone, 390. Asellidas, 312, 303, 314, 371, 372, 430, 43L Asellodes, 319. alta, 319, 321. Asellotes homopodes, 37L Asellus, 301, 313, 415. communis, 314. Gronlandicus, 315, 319. Astacilla, 361, 297, 301, 363, 431. Americana, 364. grannlata, 364, 362, 429, 434. longicornis, 362, 363, 366. Basis, 300. Bate, C . Spence, on the incubatory pouch, 302. Bate, C. Spence, on terminology of Crustacea, 300, Bate and "Westwood, on 2Ero-spirantia, 305. [302. Anceus, 409. Anthura, 398. Anthura gracilis, 401. British Isopoda, 429. Idotea tricuspidata, 345. Ja3ra albifrons, 318. Limnoria, 372. Paranthura, 402. Tanaia, 416. Tanais Edwardsii, 422. Bathynomus giganteus, 383. BopyridaB, 311, 377, 429, 431. Bopyrus, 312, 43L abdominalis, 312. Hippolytes, 311. Mysidum, 312. species, 312, 428, 433. Brevoortia menhaden, 391. Bnllar, J. P., hermaphroditism in Cymothoidae, 391. Cancer maxillaris, 410. Carpus, 300. Cepon distortus, 311, 428, 433. Ceratacanthus, 393. Chaetilia, 336. Chela, 300. Chelnra terebrans, 371, 376, 419, 423. CMridotea, 337, 300, 335, 336. cceca, 338, 335, 340, 429, 433. entomon, 337. Tuftsii, 340, 429, 433. Cirolana, 378, 376, 383, 431. concharum, 378, 298, 428, 434. polita, 381, 429, 434. truncata, 430. Cirolanidae, 376, 303, 382, 430, 43L Cleantis, 336. Ccecidotea, 314 Coldstream, J., on Limnoria, 372. Conilera, 376, 378. concharum, 378. polita, 38L Cordiner, C., on Astacilla, 363. Coxa, 300. Crossnrns, 416. vittatus, 416, 418. Cuma, 415. Cymothoa, 383, 391. oestrum, 377. ovalis, 395. prasgustator, 391. 459 460 REPORT OF COMMISSIONER OF FISH AND FISHERIES. Cymothoae, 377. Cymothoidae, 390,300, 303, 371, 382, 430, 431. Dactylus, 300. Dajus Mysidis, 312, 429, 433. Dana, J. D., on Asellidse, 314. Desmarest, A. G., on Idotea tricuspidata, 345. Digital process, 300. Dohrn, A., on Anceus, 409. the incubatory pouch, 301, 303. Tanaidse, 415. Edriophtholma, 297. Edwards, H., on Idotea tricnspidata, 345. Limnoria, 371. Tanais, 416. Epelys, 357, 301, 337. montosua, 359, 429, 434. var. hirsutus, 360. trilobus, 358, 429, 434. Epimera, 300. abdominal, 392. Erichsonia, 354, 337, 361. attenuata, 356, 335, 428, 434. filiformis, 355, 428, 434. Eurycope, 332, 329. cornuta, 333. robusta, 332, 429, 433. Flagellum, 298. Fleming, J., on Astacilla, 363. Gadus, 386. Gammarus Dulongii, 416. Gegenbaur, C., on Tanaida, 415. Gelasimus pugilator, 311. Geographical distribution, 428. Gnathia, 410, 297, 302, 357, 431. cerina, 410, 429, 435. termitoides, 410. GnathiidfB, 408, 300, 301, 303, 431. Gnathium, 410. Gnathopoda, 300. Goodsir, H. D. S., on Astacilla, 363. Gribble, 375. Gyge, 431. Gyge Hippolytes, 311, 429, 433. Helleria, 305. Henopomus tricornis, 322. Hesse, E., on Anceus and Praniza, 409. Hippoglossus, 382, 386. Hippolyte Fabricii, 311. polaris, 311. pusiola, 311, 312. securifi'ons, 311, 312. spinus, 311, 312. Huxley, T. H., distinction of cephalic and thoracic Ideotea marina, 344. [segments, 302' Idotea, 341, 337, 431. acuminata, 344. Basteri, 343. bicuspida, 352. cceca, 338. entomon, 345. filiformis, 355. irrorata, 343, 342, 348, 429, 430, 433. marina, 344. marmorata, 352. metallica, 349, 350. montosa, 359. Idotea nodulosa, 352. pelagica, 343, 345, 346. phosphorea, 347, 342, 346, 429, 438. pulchra, 352. robusta, 349, 342, 429, 433. tricuspidata, 343, 345, 346. tricuspis, 344. tridentata, 344, 345. Tuftsii, 340. variegata, 343. Idoteidae, 335, 301, 303, 361, 397, 430, 43L Idothea balthica, 344, 346. nodulosa, 351. pelagica, 344. robusta, 349. Hyarachna, 334, 329, 335, 429, 433. Incubatory pouch, 301. Ischium, 300. Isopod, length of, 302. Isopoda, 297. aberrantia, 303. Jsera, 314, 301, 313, 430, 431. albifrons, 315, 318, 429, 430, 433. Baltica, 315, 318. copiosa, 315. Kroyeri, 315, 318. maculata, 315, 318. marina, 315, 318. nivalis, 315, 318. triloba, 358. Janira, 319, 313, 430, 431. alta, 321, 299, 429, 433. laciniata, 324. maculosa, 319, 322. epinosa, 323, 429, 433. Johnston, G., on Astacilla, 362. Ejnahan, J. K., on Actsecia, 309. Kroyer, H., on Antliura carinata, 401. Munna, 325. Tanais Edwardsii, 422. Labium, 300. Labmm, 300. Lamella, external of maxillipeds, 299. Latreille, P. A., on Idotea tricuspidata, 345. Leachia, 361, 363. granulata, 364,366. Leach, "W. E., on Gnathia, 410. Leacia, 361, 363. Legs, 300. Leidya distorta, 311. Leidy, J., on Bopyrus species, 312. Cepon distortus, 311. Leptochelia, 420, 301 r 414, 415, 43L algicola, 421, 429, 435. coeca, 427, 429, 435. Edwardsii, 416, 421, 422, 423. filum, 426, 429, 435. limicola, 424, 429, 435. minuta, 416. rapaz, 424, 423, 429, 435. Leptophryxns Mysidis, 312. Ligia, 305, 310, 311, 415. LiLjeborg, "VV., on Jaera albifrons, 318. Limnoria, 373, 313, 371, 419, 430, 43L lignornm, 373, 423, 429, 430, 434. ton-brans, 373. ALPHABETICAL INDEX. 461 limnoria uncinata, 374, 376. xylophaga, 37L Limnoriadae, 371. Limnoriidae, 371, 303, 431. Lironeca, 395. Livoneca, 394, 383. ovalis, 395, 300, 428, 434. Lockington, "W.N., on color of Idotea pulchra, 353. Loligo Pealii, 394. Macdonald, J. D., on Tanais vittatras, 417, 419. Mancasellus, 313. Mandibles, 299. Maxilla, 299. Maxillipeds, 299. Mayer, P., Hermaphroditigm in Cymothoidse, 391. Meinert, F., on Idotea tricuspidata, 846. Merus, 300. Mesostenus, 334. Metzger, A., on Jsera albifrons, 318. Mieropogon nndulatus, 396. Mobius, K., on Jaera marina, 318. Molar process, 299. Montagu, G., on Oniscus gracilis, 401. Miiller, F., on Bopyridae, 30:;, 311. Leptochelia and Paratanais, 420. olfactory setae, 298. Tanaidse, 303, 415. Tanais Edwardsii, 423. Mullet, 394. Manna, 325, 313, 430, 431. Boeckii, 325, 328. Fsvbricii, 325, 429, 433. Munnopsidae, 328, 303, 314, 430. Monnopsis, 329. typica, 330, 334, 429, 433. Nerocila, 391. munda, 392, 428, 434. Norman, A. M., British Cymothoidae, 430. Ocelli, 298. Olfactory setae, 298. Oniscidse, 305, 303, 311, 314. Oniscoidea, 314. Oniscus albifrons, 315. Balthicus, 344. creruleatus, 410. entomon, 344. gracilis, 401. marinus, 318. praegustator, 391. psora, 384, 386. Operculum, 302,336. Ourozeuktes, 377. Palaemonetes vulgaris, 312. Palpus, 299. Pandalus borealis, 312. Montagui, 312. Paranthura, 402, 398, 43L arctica, 405. brachiata, 402, 429, 435. costana, 405. norvegica, 404. tennis, 406, 407. Paratanais, 416, 420, 431. algicola, 419, 42L ca-ca, 427. forcipatus, 423. Paratanais limicola, 424, 427. Peduncle, 298. Pereion, 298, 300. Pereiopods, 300. Pleon, 298, 301. Pleopods, 301. Philoscia, 305. vittata, 306, 429, 43& Phryxus, 431. Phryxus abdominalis, 312, 429, 433. Hippolytes, 312. Pill-bug, 298, 305. Platyarthrus, 308. Pomatomus saltatrix, 396. Porcellio, 305. Praniza, 409, 410. cerina, 410, 412. cceruleaia, 410. Reinhardi, 413. Propodus, 300. Ptilanthura, 405, 398. oculata, 408. tenuis, 406, 429, 435. Raia, 386. Rathke, H., on Crossurus, 416, 417. Respiration, 302, 303. Rostrum, 302. Salve-bug, 384. Sars, G. 0., on Eurycope, 332. Dyarachna, 334. Munnopsidae, 329. Munnopsis, 331. Sars, M., on Idotea tricuspidata, 346. Jaera albifrons, 318. Munnopsidae, 329. Munnopais, 331. Schiodte, J. C., on Anthura, 397. Artystone, 390. Cymothoae, 377. Scyphacella, 307. arenicola, 307, 428, 433. Scyphax, 307. omatus, 309. Serolids, 304. Smith, S. I., list of Bopyridae, 311. Limnoria xylophaga, 371. Scyphacella, 307. Sow-bug, 298, 299, 305. Sphaeroma, 368, 301, 367, 372, 430, 431. quadridentatum, 368, 429, 434. eerratum, 430. Sphaeromidaa, 367, 303, 431. Stebbing, T. R. R., on AstaciUa, 362. British Arcturidaa, 430. Dynamene rubra and viii* dis, 430. Tanais vittatus, 417,419. Stenosoma flliformis, 355. irrorata, 343. Stenotomus argyrops, 396. Stimpson, "W., on Anceus americanns, 410, 413. Asellodes, 319. Cirolana concharum, 38L Cirolana polita, 381. Praniza cerina, 412, 413. Tanais fllum, 426. 462 REPORT OF COMMISSIONER OF FISH AND FISHERIES. Synidotea, 350, 337. bicuspida, 352, 429, 433. nodulosa, 351, 299, 347, 429, 433. Syscenns, 387, 383, 391. infelix, 387, 429, 434. Tanaida, 415. Tanaidse, 413, 298, 300, 302, 303, 304, 43L Tanais, 416, 297, 301, 414, 415, 431. Cavolinii, 416, 419. Dulongii, 416. Edwardaii, 416, 421, 423. filum, 420,421,423,426. hirticaudatns, 418. islandicus, 428. Sarignyi, 423, Tanais, tomentosus 418, 419. vittatns, 418, 417, 420, 428, 429, 431, 435. Telson, 301. Templeton, K., on Zeuxo, 416. Tetradecapoda, 297. Thorax, 298, 300. Tylns, 305. TJropods, SOL Verrill, A. E., on CMridotea Tuftsii, 34L Venns mercenaria, 359. "Westwood, J. O., on Anisocheirus, 416. White, A., on Limnoriadae, 37L "Willemoes-Suhm, R. v., on Tanais, 418L "Wood-lice, 305. Zeozo Westwoodiana, 416. .- ,->r- .'i.'.i [Report of the United States Commissioner of Fish and Fisheries. Part vi. For 1878. Opposite page 4(52.] ERRATA. Page 313, line o, for 79 read 371. 329, tt f ; <>; " 383, " 22, " 23, " 20, " 38 89 " 332. " 334. " 383. 93 " 387. " 398, " 9, " 104 " 398. " ; " 11, " 108 " 402. " ' < 12, " 111 " 405. 416, 35, " 122 " 416. 't (( it 36, " 126 " 420. " 431, " 33, " 139 " 433. . , 1 1 tt Ci 141 435. 435, last line. " 137 " 431. In partial explanation of the above list of incorrect references, the author has to say that he had no opportunity of seeing a correctly paged proof of the article during the year that it was in press at the Government Printing Office. 0. H. >/ [PROM THE AMERICAN JOURNAL OF SCIENCE AND ARTS, VOL. XV", MAY. 1878.] Descriptions of new Genera and Species of Isopoda. from New England and Adjacent Regions ; by OSCAR HARGER. Brief Contributions to Zoology from the Museum of Yale College. THE genera and species described in the present paper are, except the first, marine and were, mostly, collected by the United States Fish Commission, along the New England coast. More complete descriptions with figures of all th'e new, and most of the old species, are nearly ready