in the Museum of the Smithsonian Institution. 123 



and Soutli Carolina, Georgia, Florida, etc. It burrows in the 

 sands about low-water mark, its holes being usually about one 

 foot in depth. 



ASTACOIDEA. 



!*!tcyBlarMs nodiler. 



Scyllarus nodifer Stimpson, Proc. Chicago Acad, of Sciences, I, 48. 



Upper surface tuberculated ; tubercles sparsely setose. A strong, 

 bidentate projection on the gastric region of the carapax. On the 

 third segment of the abdomen above there is a very prominent, me- 

 dian knob, which forms the posterior extremity of the body when the 

 abdomen is folded in. The second joint of the antenniB is armed 

 with four or five teeth on the antero-exterior margin — the teeth, with 

 the exception of that at the angle, being little prominent. Fourth 

 joint of the antennae broader than long, with the margins crenulated, 

 and the antero-exterior angle prominent. 



The length of the largest specimen is about five inches. In a male, 

 the length of the carapax is 2.1 ; and its breadth at the anterior ex- 

 tremity, 1.88 inches. In a female, length of carapax, 1.225; breadth 

 anteriorly, 1.13 inches. 



Found among the Florida Keys. The specimens in the 

 Smithsonian Museum were taken at the Tortugas by Dr. 

 Whiteliurst, and there are examples from Key West in the Mu- 

 seum of Comparative Zoology at Cambridge. 



CAEIDEA. 

 Hippo! ysiBiata .caMrorisica. 



Hippolysmata californica Stimpson, Proc. Chicago Acad, of Sciences, I, 48. 



Surface of carapax and abdomen minutely pubescent. Rostrum 

 short, scarcely over-reaching the ante-penult joint of the peduncle of 

 the antennulifi, and six-toothed above, the posterior tooth being situ- 

 ated at one-half more than the usual interval behind the next tooth, 



