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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 37. 



The abdomen is composed of a single segment, the posterior margin 

 of which is trilobate, the median lobe being the largest. The uropoda 

 are missing in both specimens. The seven pairs of legs are similar in 

 the female and terminate in bi-unguiculate dactyli. In the male, 

 however, the first pair of legs is prehensile, with propodus and dac- 

 tylus dilated, the propodus fringed with long hairs. 



Only two specimens, a male and a female, were collected by the 

 U. S. Bureau of Fisheries steamer Albatross at station 2770, off the 



FlG. 1.— NOTASELLUS TRILOBATUS. d, FEMALE, X 19 J; 6, FIRST LEG OF MALE, X 19gJ C, FIRST 

 AND SECOND PLEOPODS OF MALE, X 30§. 



east coast of Patagonia, lat. 48° 37' S., long. 65° 46' W., at a depth 

 of 58 fathoms in gray sand with black specks. 



This species is close to the two first-mentioned species of the genus, 

 but differs in the shape of the abdomen, of the first pair of legs of the 

 male and of the distal extremity of the outer branch of the second 

 pleopoda of the male, in the more rounded antero-lateral angles of 

 the head, and the less protruding eyes. 



Type.— Cat. No. 40099, U.S.N.M. 



