158 Natural History Bulletin. 



deep, pure red,^ a few having yellow markings. I have no 

 recollection of any other species with any considerable amount 

 of blue. Cryptopodia concava Stimp.^ is found both on the 

 Bahama Banks and on the Pourtales Plateau. 



About a dozen species of Cancroid crabs were collected 

 here, representing as many genera. The largest species was 

 Bathyncctes longispina Stimp., which derives its name from 

 the long spine projecting from the lateral angle of the cara- 

 pace. Four smaller spines are found between it and the eye. 

 and each of the last four joints of the chelipeds bears a spine 

 on its upper front margin. A minute species of Calappa, C. 

 angnsia (M. E.), was dredged in about eighty fathoms not far 

 from Key West. Osochila tiiherosa Stimp. is peculiar in hav- 

 ing the entire lower surface of the bod}^ and mouth-parts cov- 

 ered with irregular pits, giving a honey-combed appearance. 

 Probably the most abundant crab on the Pourtales Plateau is 

 the little CycJodorippc nitida A. M. Edw., which came up by 

 the score at nearly every haul in the Gulf Stream. The gen- 

 eral color is bright red, varied with white, and the surface is 

 smooth and glossy. It is one of the species discovered by the 

 '•Blake.'' CyniopoJiis aspcr A. M. E. is another '"Blake" spe- 

 cies, with an exceedingly hispid surface and a considerable 

 portion of the abdomen visible from above. 



But three species of Anomuran crabs were collected in this 

 region. One was the hermit crab Ccuohita diogcncs Latr., 

 almost omnipresent on the sandy ke\s. especially Sand Key 

 proper, where a bucket full was collected in a short time. 

 The exposed portions of these animals are most brilliantly 

 colored, the large claw being a clear dark blue, while the 

 other exposed feet are bright red. Their favorite habitation 

 seems to be the shell of Astraliiiui ccelattini Gmel., which is 

 abundant here. This is, in fact, a hermit crab which has 

 adopted a terrestrial habit almost, if not quite, as complete as 



'Professor \'errill thinks that the red color, on account of the actinic 

 properties of the pale-green light at great depths, is protective, only 

 appearing bright when exposed to daylight. 



^See p. 51. 



