68 Bulletin, Va^iderhilt Marine Museum, Vol. Ill 



tory, the Philadelphia Academy of Natural Sciences, the Smithsonian 

 Institution, the Paris Museum and the Museum at Petrograd, 



Distribution : "West coast of the Americas from California to Chile. 



Material examined : One ovigerous female taken at Punta Arenas, 

 Costa Rica, March, 1928, by the "Ara," William K. Vanderbilt, 

 commanding. One, Perlas Islands, March, 1928. 



Technical description : Carapace oval, shuttle-shaped, but wider 

 in proportion to its length and not so high as is E. emerita. The pres- 

 ent species is 19 mm. long, 16 mm. maximum width; with numerous 

 fine, wavy, transverse imbrications over the entire dorsal surface; 

 there is a short, deep, transverse line just behind the rostral region 

 and a pair of small, crescentic pits on each side of the median region. 

 The frontal margin is quite different from that of E. emerita. There 

 are two rounded, submedian teeth separated from each other by a 

 shallow, U-shaped sinus on either side at the base of the eye, beyond 

 which the carapace is again produced and rounded similar to the 

 submedian teeth and then slopes backward to the lateral margin, which 

 is convex, deeper and in the hinder two-thirds almost or entirely 

 concealing the meral joints of the legs. The abdomen has the first 

 segment linear, narrow, subcrescentic ; the second segment is nearly 

 as wide as the carapace and has the lateral plates twice as long as 

 is the segment in the median line, and evenly rounded ; there are two 

 transverse grooves on each epimeral plate, one placed nearly me- 

 dially and the other just anterior to the posterior margin ; neither of 

 these grooves is continuous across the median region of the segment 

 and both are set with a row of stiff, short setae. The third segment 

 is only slightly wider than the median part of the second segment and 

 not quite as long, with the anterolateral angle subacute and the lat- 

 eral margin convex, sloping posteriorly ; the fourth segment is shorter 

 and narrower than the third, with the epimeral region forming an 

 acute point anteriorly; the fifth segment is similar to the fourth but 

 smaller and with the anterolateral angle more acute ; the epimera of 

 the third to fifth segments, inclusive, are heavily plated and carinated, 

 the anterior margin of each of these segments bears a row of short, 

 stiff setae ; the sixth segment is nearly three times as long as the 

 fifth, very convex transversely, with the vsddth narrowing posteriorly ; 

 the uropoda have an elongate, curved peduncle, which is about half as 

 wide as long, the blades are distinctly unequal, the outer blade nearly 

 a third longer than the inner and narrower, elongate-ovate ; the inner 

 blade shorter and much wider in proportion to its length, both blades 



