104 Proceedings of the Biological Society of Washington. 



Pinnixa vanderhorsti, sp. nov. 



Holotype. — Male; Spanish Harbor, Curasao. 



Measurements. — Male holotype, length of carapace 3.4 mm., width 6 mm. 



Description. — Carapace narrowing toward the sides, smooth, punctate, 

 without posterior ridge; lateral marginal line disappearing toward hepatic 

 region. Front curved downward and fringed with hair. Orbits in dorsal 

 view inclined forward and outward. Chelipeds small, upper half of outer 

 surface hairy; a longitudinal ridge through middle of manus; fingers hori- 

 zontal. Legs broad, third pair much the largest. Terminal segment of 

 abdomen semi-oval, its proximal end only slightly broader than the contigu- 

 ous portion of preceding segment. 



Pinnixa arenicola, sp. nov. 



Holotype. — Male; Spanish Harbor, Curagao. 



Measurements. — Male holotype, length of carapace 3 mm., width 6 mm. 



Description. — Allied to the preceding. Posterior margin of carapace 

 longer, antero-lateral region higher; front narrower, sides more convergent; 

 cornea smaller. Propodus of third leg narrower at proximal end, dactylus 

 slenderer and more curved. Third segment of abdomen transversely 

 oblong, proximal and distal margins slightly bilobed by a median emargin- 

 ation, sides faintly sinuous; fourth segment very broad, having two trans- 

 verse crescentic wings united medially by a very narrow neck; fifth and 

 sixth segments together urn-shaped. 



