Chlorodio Affinis, Carapace Angustiore, Suborbiculato, Articulo Maxilli- Pedum Externorum Tertio Triangulato, Paulo Transversa, Latere Interiore Brevissimo
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surface of hand scarcely seriate, under surface of hand glabrous, fingers channeled, the upper spinulous above. Eight posterior feet hirsute, excepting sides of third joint, upper margin of third joint spinulous. Plate 12, fig. 10 a, outline of antero-lateral margin; b, front view of front and base of outer antennae; c, outline of back. From the Sooloo Sea, or Balabac Passage. In the pilumnoides, as described and figured by White, the antero- lateral margin has distinct teeth, and although consisting of spinules in part, there is a prominent or dominant spine. In our specimens, the five normal teeth may be distinguished, though much subdivided into smaller teeth, and irregularly so; D consists of two teeth; E of two; N of four; T of three, with two or three on the surface above; S of one, with one or two on the upper surface. D and E are so close together that they appear at first to make a single group. The mi- nute tubercles of the anterior part of the carapax are somewhat acute, or like short spinules on the areolets near the antero-lateral margin. The surface of the carapax is hairy, but nearly naked posteriorly, and the legs are rather long hairy; the hairs are like bristles, and many of them black in their lower half, but become light-coloured in their upper half. The anterior margin of the arm has about three small teeth on its lower half, and is hardly denticulate above, instead of having prominent teeth, towards apex, as in the figure by Adams and White. Chlorodius pilumnoides, ADAMS and WHITE, Crust. Voy. Samarang, 41, pi. 9, f. 3. GENUS CYCLODIUS. Chlorodio affinis, carapace angustiore, suborbiculato, articulo maxilli- pedum externorum tertio triangulato, paulo transversa, latere interiore brevissimo. Near Chlorodius. Carapax narrower, suborbicular; third joint of outer maxillipeds triangular, a little transverse, the inner side below fourth joint very short. CANCROIDEA. ^223 The body in the species of this genus, appears very nearly circular, as the base of the abdomen projecting behind the carapax, in the natural state of the parts, added to the length of the carapax, very nearly equals the breadth of the carapax. The areolation of the carapax, in the species seen, is very similar to that of C. ungulatiis and G. monticulosus, both for the anterior and posterior parts of the surface. The process of the front adjoining the outer antennae is short and broad, as in Chlorodius, rather than like the same in Pilo- dius. The third joint of the outer maxillipeds is shorter than long, and-the terminal side is the longest of the triangle; this side is notched for the insertion of the fourth joint, and also exterior to this joint, very much as in Chlorodius. CYCLODIUS ORNATUS. Carapax nudus, parce nitidus, antic* posticeque valde areolatus, areolis scepe compositis, 2 M subdivisd, 3 M tripartita; margine antero-laterali tj-dentato, dentibus tumidis, apiculatis, dente E minore, rotundato, D obtuso. Pedes spinulis armati, 8 posticis parce pubescentibus, manu seriatim spinulosd, digitis spinulosis. Carapax naked, somewhat shining, anteriorly and posteriorly areolate, • areolets often compound, 2M subdivided, 3M tripartite; antero- lateral margin five-toothed, teeth tumid, apiculate, tooth E smaller than the others, D obtuse. Legs all armed with spines, posterior eight sparingly pubescent, hand seriately spinulous, fingers spinu- lous. Plate 12, fig. 11a, animal, enlarged three diameters; b, profile of front part of carapax; c, under view of anterior part of body; d, front view of front, showing process p in this view; e, view of lateral portion of ventral carapax, showing the areolation; /, abdomen, en- larged; g, hand. Sooloo Sea, or Balabac Passage, north of Borneo. Length of carapax, three and a half lines; greatest breadth, four and one-third lines; ratio of length to breadth, 1 : 1*25. The areolets CRUSTACEA. are very prominent, and broken much as in Chlorodius monticulosus. The abdomen has the last segment triangular, and a little oblong; the third joint abruptly broader than either the second or fourth, and on either side triangular. CYCLODIUS GRACILIS. C. ornato aspectu areolisque similis, parce latior, dentibus anterodate- ralibus tribus posticis tenuioribus et bene acutis, areolis vix compositis, 2M subdivisd, 3 if vix tripartita. Pedes armati, 8 posticis paulo pubescentibus, manu seriatim spinulosa, digitis spinulosis. Near ornatus in appearance and areolation, but sparingly broader, three posterior antero-lateral teeth more slender and neatly acute, areolets hardly compound, 2M subdivided, 3M scarcely tripartite. Feet armed, eight posterior a little pubescent, hand seriately spinulous, fingers spinulous. Plate 12, fig. 12 a, animal, enlarged three diameters; b, leg of pos- terior pair, enlarged. From Tutuila, Samoan Group, Pacific. Length of carapax, three lines; greatest breadth, four lines; ratio of length to breadth, 1 :1'33. The abdomen and hands in this species, are the same very nearly as in the ornatus (see figures/and g of that, species). The posterior legs are also similar; yet the spinules appear to be a little more pro- minent. It is possible that this may be only a variety of the ornatus. GENUS CYMO, Dc Haan. The species of Cymo have a very peculiar aspect, the body being flattened, and approaching orbicular in outline, and the larger hand rather long, with very stout fingers, the upper much curved. The front margin is equal to half the whole breadth of the carapax, and there is no point of separation between the antero-lateral and postero- CANCROIDEA. ^225 lateral margins. The species are small, the largest seen being about half an inch in length. CYMO MELANODACTYLUS, De Haan. Carapax vix areolatus, partim subtilissime pubescens, lateribus convexis, sive non dentatis sive obsolete 2-3-dentatis, fronte denticulato, dentibus acutis fere acquis. Pedes antici multo granulati, digitis nigris, valde scabris. Pedes 8 postici hirsuti. Carapax hardly at all areolated, in part having an exceedingly short pubescence, sides convex, either not dentate or with two or three obsolescent dentations, front rather evenly denticulate, the teeth acute. Anterior feet much granulous, fingers black, scabrous. Posterior eight feet hirsute. Plate 13, fig. 1, male, enlarged three diameters. Feejee Islands. Length and breadth of carapax of a male, each five lines. The teeth of the front margin are six in number, with an intermediate smaller one in one or two of the intervals. On the lateral margin towards the middle there are two obsolescent teeth. The granules of the hand are very closely set, and in two lines are somewhat seriate and more raised. The hand is rounded above; one of the specimens is a female, with eggs beneath the abdomen. The smaller hand has rather slender fingers, and they are in contact. The male abdomen appears to be five-jointed. Cymo melanodactylus, DE HAAN, Faun. Japon., 22. CYMO ANDREOSSYI (Savigny) De Haan. Digitus manus majoris mobilis albus, Icevis, juxta basin paulo scaberf crassus. Frons irregulariter denticulatus. 57 CRUSTACEA. 235 Moveable finger of larger band white, smooth, a little scabrous near base, stout* Front irregularly denticulate. Plate 13, fig. 2 a, male, enlarged three diameters; b, under view of front, showing base of outer antennas. Upolu, Samoan Group; also Tahiti, Society Group. Length and breadth of carapax of a male, each six lines. The re- semblance to the preceding species is very close, although the two are separated easily by the characters stated. The anterior part of the lateral margin is rather shorter than the posterior. The granules of the hand in the dried specimen are partly white and partly reddish, the red ones scattered among the others. Pilumnus Andreossyi, SAVIGNY, Desc. de l'Egypte, Crust., p. 80, pi. 5, f. 5. Cymo AndreossyiDE HAAN, Faun. Japon., 22. SUBFAMILY POLYDECTINIE. GENUS POLYDECTUS, Edioards. The species here referred to Polydectus has many characters in common with the P. cupidifer, and the two, evidently, are congeneric. Besides general form and aspect, one of the most striking charac- teristics is the peculiarity of the hand, which is hardly stouter than the following legs, and although short, consists of long, slender fingers, the palm at the base of the fingers being very short. Moreover, these fingers are nearly equal, and have the apices incurved. Another character in common is observed in the orbit, there being three tubercles or lobes forming the under and outer part of the orbital margin; in the ciqmlifcr these prominences are hollowed out,—a spe- cific and not a proper generic distinction. The genus Polydectus was transferred to the Corystida? bv Milne Edwards, from the genus Pilumnus, where it was placed originally by Latreille. The character of the outer antenna1, especially the slender, nearly naked flagellum, removes it from the Corystidce; and it is not related particularly to that family in the form of the outer maxilli- peds. The second joint of these organs is somewhat transverse in our CANCROIDEA. ^227 species, and but little oblong in the cupulifer; moreover they neatly close up the buccal area. It appears to be most closely like the Can- croidea, and may come near Pilumnus, or near Halimede. Still it differs widely from Halimede, as already explained. The specimen from which our figure and description were taken, was lost, with others of the same region, in the wreck of the Peacock; and we cannot, therefore, resolve our doubts with regard to the cha- racter of the palate, which would definitely fix its true place. It is probable that the genus should form a subfamily distinct from any other described Cancroidea, and so we have made it; but its place with the Cancridae rather than the Eriphidae is hypothetical. PoLYDECTUS VILLOSUS. Carapax pedesque densissime villosi, pilis plumiformibus, fronte mar- gineque antero-laterali integris. Digitus mobilis paris antici duabus spinis elongatis remotis et alter spinis tribus armatus.