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PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxvi. 



posterior margins of the head and a distance from the lateral margin 

 equal to the width of one eye. The first pair of antennae have the 

 first article large; the second is about one-half as large as the first; 

 the third is as long as the second, but narrower ; the fourth is half as 

 long as the third; the fifth is a little longer than the fourth; the 

 sixth and seventh are subequal and only about half as long as the 

 fifth. The second antennae have the first article very short; the 

 second is about three times longer than the first ; the third is quite 

 long, about three times longer than the second ; the fourth and fifth 

 are about equal in length and each is a little shorter than the third; 

 the flagellum - is composed of twelve articles. The antennae are gen- 

 iculate at the articulation of the third and fourth articles. 



The first and fourth segments of the thorax are subequal in length ; 

 the second and third are subequal and are the longest ; the fifth is the 

 shortest; the sixth and seventh are subequal and are a little longer 

 than the fourth but not quite as long as the third. The sides of the 

 segments are almost straight and the epimera are not indicated. 



The abdomen consists of a single segment. The posterior margin 

 is deeply excavate on either side of an acute median point. The 

 post-lateral angles are also acute. About one-third the distance from 

 the post-lateral angles the sides of the abdomen are produced in a 

 small, but pronounced tooth, just above a small excavation in the 

 lateral margin. The uropoda are placed in the posterior excavations 

 of the posterior margin, and consist of a large peduncle, about twice 

 as long as wide, and a minute inner branch, tooth-like, and an outer 

 branch, which in a dorsal view is apparent only as a bunch of hairs. 

 In a ventral view the outer branch is placed in an excavation, is 

 minute, and does not reach beyond the posterior margin of the 

 peduncle. 



The legs are all similar and terminate in biunguiculate dactyli. 



Three specimens, all females, come from U. S. Bureau of Fisheries 

 station 2770, east coast of Patagonia. They were collected by the 

 steamer Albatross at a depth of 58 fathoms in gray sand and black 

 specks. 



Type.— Cut. No. 39240, U.S.N.M. 



