CRUSTACEA. 



Nassau Bay, Fuegia. 



Length of carapax, two and five-eighths inches ; of beak, five-eighths 

 of an inch ; anterior pair of legs, exclusive of hand, nearly as long 

 as carapax ; hand, two-thirds as long as carapax ; thigh of second 

 pair of legs, very nearly as long as carapax; whole leg, nearly two 

 and a half times as long as carapax. The carapax has the two 

 spines of the medial region prominent, and one small spine either 

 side of the anterior. The lateral regions have a spine nearly in 

 a line with the post-cardiac, and another smaller, forward and inward 

 of this one ; also, over the base of second pair of legs, two small spines. 

 Posterior to the post-orbital spine, there is a tumid prominence in 

 the sides of the carapax, and a small obtuse spine on the upper 

 side of this prominence. Between the post-cardiac spine and the 

 marginal behind, occupying the intestinal region, there is a low pro- 

 minence with two obsolescent spines. The rounded tooth on the 

 inner edge of the finger stands isolated ; the rest of the edge is thin 

 and denticulate. The third joint of the eight posterior legs is thinner 

 below and has a series of small rounded points or tubercles. The 

 posterior margin of the inner-antennary cavity, next to the outer 

 antennae, is reflexed downward, and a process from the base of the 

 outer antennae extends inward just anterior to this reflexed piece. 



This species is near the Audouinii ;* but the upper surface of the 

 beak is flattened, and the fifth joint of the eight posterior legs is longer 

 than the fourth, instead of shorter. The length of the hairs on the 

 lower edge of the fifth joint of the eight posterior legs, is not one- 

 fourth the breadth of the joint, while it is one half the breadth in the 

 Audouinii. The third and fourth joints of these legs also are not as 

 nearly cylindrical. 



Eurypodius septentrionalis, DANA, Sill. Am. J. Sci., 2d Ser., ix. 270. 



* D'Orbigny, Voy. dans L'Amerique Merid., Crust., p. 3, pi. 1. The specific descrip- 

 tion of the E. Audouinii and the drawing, represent the fifth joint as shorter than the 

 fourth ; while the remarks following the specific description make it longer ; the last 

 is evidently an error. 



