78 Notes on North American Crustacea. 



HIPPIDEA. 

 Albunaea Gibbesii, nov. sp. 



Plate I., fig. 6. 



Albuncea symnista, Gibbes ; (non Fabr.) loc. cit. p. 18Y. 



Carapax broader than long, and considerably broader than in A. 

 symnista. Ocular peduncles elongated, sharply triangular as in A. 

 Paretii ; their inner edges straight ; their outer edges scarcely at all 

 convex. Anterior margins on each side denticulated with six or eight 

 teeth, variable in size, sub-distant and rather short. The tooth or spine, 

 at the antero-lateral angle, reaches forward but little beyond the level of 

 the anterior margin of the carapax, and is far shorter than in A. Lucasii. 

 Dactylus of fourth pair of feet with no projecting lobe at the superior 

 base ; extremity acute, not rounded as in A. symnista. The terminal 

 joint of the abdomen, in the male, is narrow, and acuminate, its extremity 

 forming a long narrow projection, equalling one-fourth the entire length 

 of the joint. This projection and the lateral margins of the joint are 

 soft and flexible. On the surface of the joint there is a thick longitudi- 

 nal tuft of longish setse on either side of the median line, also a very 

 thick tuft or pencil on each side at the base. Length of carapax in the 

 male, 0*95 ; breadth, 1*10 inch. 



This large species resembles A. Paretii in its front and eyes, 

 but differs mucli in the characters of the last joint of the male 

 abdomen. 



Found at St. Augustine, Fla., by J. C. H. Smith, Esq. It 

 also occurs among the Keys, near the southern extremity of 

 Florida. 



