STALK-EYED CRUSTACEA 249 



large, and their floor slopes outwards and downwards. 

 The antennulary fossai are oval, small, and divided by 

 a small triangular prolongation of the epistome. The 

 external antennae occupy the internal canthus of the orbit. 

 The buccal cavity is rhomboid in form. The third and 

 the fourth joint of the external maxillipedes are 

 quadrilateral, almost of the same size, and their internal 

 border forms a straight line, so that, when in place, there is 

 no lozenge-shaped space between them ; the fifth joint is 

 articulated at the external angle of the fourth, and rests, 

 exposed, upon its anterior border. The fingers of the 

 first pair of legs are broad, and their tips slightly 

 excavated. Of the walking legs, the terminal joint is 

 compressed and without spines. 



Range. — Tropical America, West Indies. 



Synopsis of the Species. 



A. A prominent ridge on the antero-lateral borders of 

 the carapace. 



a. Pterygostomian regions granular. 



1. Under border of walking legs with long, close, 

 black-brown hairs. Notch in last joint but one of 

 abdomen of female to receive terminal joint, not so 

 deep as length of last joint — (17. cordafa.) 



2. Under border of walking legs with only three or 

 four scattered hairs. Notch in last joint but one 

 of abdomen of female to receive terminal joint as deep 

 or deeper than length of last joint. — {U. tina^ 



B. Antero-lateral borders of carapace scarcely in- 

 dicated. 



b. Pterygostomian region smooth. — {U. Icevis?) 



