1879.] NATURAL SCIENCES OP PHILADELPHIA. 405 



that the two posterior pairs of feet and the projecting abdomen 

 each do their part. 



PORCELLANOIDEA. 



Family POCELLANIDiE. 

 Genus PETROLISTHES Stm. 1 

 Petrolisthes sexpinosus Stm. 



Porcellana galathina Say, 1. c, i. p. 458 ? (non Bosc). 

 Porcellana sexspinosa Gibbes, Proc. Am. Assoc, iii. p. 190. 

 Petrolisthes sexpinosus Stm., Proc. Phila. Acad., 1858, p. 227. 



Professor Webster collected specimens at Key West, Harbor 

 Key, Florida Bay, and Sarasota Bay. 



I am inclined to follow Stimpson in supposing that this is not 

 the Porcellana galathina of Bosc, as it differs considerably from 

 his figure, which represents a species with smaller hands, shorter 

 fingers, the ridges of the carapax different, while the carapax itself 

 is nothing like that of this species. This species has been re- 

 ported from Georgia and Florida (Say), South Carolina and Key 

 West (Gibbes) and Florida Keys (Stm.). 



Petrolisthes jugosus Streets. 



Petrolisthes jugosus Streets, 1. c, 1872, p. 134. 

 I refer, with a doubt, a single specimen collected at Key West 

 to this species, as it presents the following points of difference 

 from Dr. Streets' description : The lobes of the front are indis- 

 tinct. (The right hand is missing.) The posterior border of the 

 hand is not pubescent, and there is no trace of a furrow on the 

 upper portion of the hand ; the anterior margin of the carpus 

 has four teeth. In every other respect it agrees perfectly. Dr. 

 Streets' specimens came from the Island of St. Martins, W. I. 



1 I would here straighten the synonymy of two species of this genus 

 Petrolisthes dance- 



Porcellana bosii Dana, U. S. Expl. Exped. Crust., p. 421, pi. xxvi. f. 2 



(non Savigny). 

 Porcellana dance Gibbes, Proc. Elliot Soc'y, i. p. 11. 

 Petrolisthes braziliensis Smith, Trans. Conn. Acad., ii. p. 38. 

 Rio Janeiro (Dana). 



Petrolisthes Helleri. 



Porcellana dance Heller, Reise der Osterreich Fregatte Novara, Crus- 

 taceen, p. 74 (non Gibbes). 

 Nicobars (Heller). 



