30 



S. I. Smith on Brazilian Crustacea. 



organ which depends between them, and consists of a central tubular 

 portion articulated with the bases of the abdominal appendages by a 

 short process on each side and furnished at the lower extremity with 

 two stiif, horn-like, tubular processes. The central portion is open on 

 the postei'ior side for its whole length, and the membrane of which it 

 is composed is folded into deep longitudinal grooves, except on the 

 anterior side which is smooth and flattened, and traversed longitudi- 

 nally by a median suture. The horn-like, terminal processes curve 

 slightly backward and downward, and have an opening on the lower 

 side at the tips. The inner of the terminal branches of the append- 

 ages of the second abdominal segment are furnished at the base on 

 the anterior side with a small, ovoid, flattened, cushion-like organ 

 which is wanting in the appendages of the other abdominal segments, 

 and in all of those of the female. 



Three specimens give the following measurements : — 



Length of body from tip of rostrum to extremity of ab- 

 domen, ...... 



Length of carapax from orbit to middle of posterior 

 margin, ...... 



Breadth of carapax, .... 



Length of rostrum from tip to base of eyes, 



" basal scale of antenna, 



" first thoracic legs, .... 



" hand in first thoracic legs, 



" second thoracic legs, 



" hand in second thoracic legs, 



" third thoracic legs, . . - - 



" hand in third thoracic legs, 



" merus in fourth thoracic legs, 



" carpus, " " - - 



" fifth thoracic legs, . . - - 



" merus in fiftli thoracic legs, 



" carpus " " - 



" propodus " " - - 



" dactylus " "... 



" first pair of abdominal appendages, 



" second " " - - 



Several specimens of this remarkable species — all of them some- 

 what broken and in rather bad condition — were obtained by Prof. 

 Hartt at Caravellas, Province of Bahia. 



