22 NEW-YORK FAUNA — CRUSTACEA. 



Genus Callianassa, Leach. Abdomen elongated, membranous. Terminal filaments of the internal 



antenna? much longer than the peduncle. No respiratory appendices under the abdomen. 



Lateral plates of the caudal fin foliaceous and very broad. First and second pair of feet di- 



dactyle; third pair enlarged towards their extremities. 



C. major. (Say, Journ. Ac. Nat. Sc. Vol. 1, p. 235.) Hands unequal: carpus granulated, trilateral, 



not concave. Hand much elongated, sublinear, compressed, glabrous. Abdomen membranaceous, 



of six segments ; lateral lamellae simple, larger than the tail. Length, 4-5. Burrows in sand. 



Florida. 



Genus Gebia, Leach. Characters of the preceding, but the first and second pair of feet with a movable 



finger, and projecting angle for a thumb. Rostrum elongated and broad, concealing the eyes. 



G. affinis. (Say, loc. cit. Vol. 1, p. 241.) Thorax glabrous, covered in front with tufts of hair arising 



from tubercles. Rostrum short, canaliculate, hairy. Hands not broader than the carpus, linear, 



nearly equal to the third joint. Length, 2*25. Coast of Georgia. 



GENUS ASTACUS. Fabricius. 



Rostrum depressed, wide at base, and with not more than one lateral spine. Lamellar 

 appendix of the external antennae large ; the fifth thoracic ringis articulated with the 

 preceding, and not soldered to them. Six anterior feet didactyle. Exclusively fluviatile. 



ASTACUS BARTONII. 



PLATE VHI. FIG. 25. 



(STATE COLLECTION.) 



Astacus bartonii. Fab. Entom. Systematica, Suppl. p. 407. 



A. id. Bosc, Hist. Nat. des Crust. Vol. 2, p. 62, pi. 11, fig. 1. 



A. id. Say, Jour. Acad. Nat. Sc. Vol. 1, p. 167. 



A. id. Haklan, Med. and Phys. Researches, p. 230, pi. fig. 2. GoDLD, loc. cit. p. 330. 



A. affinis. Milne-Edwards, Hist. Nat. des Crustaces, Vol. 2, p. 332. 



Description. Body with scattered punctures. Rostrum mucronate, concave, elongated, 

 suddenly attenuated, but with lateral angles rather than spines at the point of attenuation. 

 No spines on the thorax. An acute triangular spine, rather exceeding the rostrum in length, 

 articulated to the outer side of the base of the external antennae ; below the base of the spine, 

 on each side, an oculiform tubercle. Movable finger slightly shorter than its opposite, and 

 a number of foveolae or pits in such a regular series on both as to produce the appearance of 

 one or more elevated lines. Carpus with a deep furrow on its upper surface, and one or 

 more spines on its inner angle. Shield with a transversal lunate furrow. The first segment 

 of the middle caudal lamella with one or two short spines on each side. 



Color of the body and claws, greenish brown ; tips of the rostrum, of the hands and feet 

 (and sexual appendices of the male), reddish. Lighter beneath. 



Total length, 2-0-3-0. 



