126 BULLETIN OF THE 



This crab, which has hitherto been found in shallow waters, but never, 

 as far as I am aware, above low-water mark, occurred to the expedition at 

 the following points and depths : — 



South of the Tortugas, January 15, 1869. Cast No. 3. 17 fathoms. 



Off Conch Reef, May 11, 1869. Cast No. 1. 30 " 



Santarem Channel, at the edge of Bahama Bank. Cast No - . 35 " 



Off French Reef, March 21, 1869. Cast No. 2. 45 " 



Subfamily ACHAEINAE. 



Podochela macrodera Stm. 

 Podochela macrodera Stimpson, Notes on N. American Crust., p. 68. 



Found at Key West, in from 2 to 5 fathoms 



Podochela gracilipes nov. sp. 



Closely allied to P. macrodera, but differs in its narrower body, longer 

 and more acute rostrum, and longer and much more slender feet. The 

 dactylus of the first pair of ambulatory feet is exceedingly slender and 

 longer than in either of the two species hitherto known, being more than 

 one third as long as the penult joint. The process of the penult joint in 

 the other ambulatory feet is almost entirely obsolete. 



Dimensions of a female : Length of carapax, 0.35 ; breadth, 0.24 inch. 



Only female specimens occur in the collection. 



West of Tortugas, January 16, 1867. Cast No. 5. 36 fathoms. 



Off Pacific Reef, May 13, 1869. Cast No. 2. 49 " 



Off Carysfort Reef, March 31, 1869. Cast No. 1. 52 " 



Off Carysfort Reef, March 21, 1869. Cast No. 5. 60 " 



Podonema nov. gen. 

 The species of this genus I formerly included under Podochela (Notes 

 on N. American Crust., p. CD), but the study of several species which have 

 since become known to me has led me to consider it distinct in the hood- 

 shaped rostrum, and in the existence of lamelliform ridges on the ptery- 

 gostomian regions, defining the afferent channels. Like Podochela, this 

 genus has a concave posterior margin of the carapax. 



Podonema Riisei Stm. 

 Podochela Riisei Stimpson, Notes on N. American Crust., p. 69. 

 A female specimen of this species was taken in 13 fathoms, off the Tor- 

 tugas. 



Podonema lamelligera nov. sp. 



The following description is that of a female, the only specimen as yet 



