NO. 1876. ON THE CRUSTACEAN ORDER CUMACEA—CALMAN. 651 



usual serrated lateral keel or line of denticles is present and ends 

 anteriorly in a strong curved tooth close to the antero-lateral margin. 

 A number of other minute denticles are scattered over the surface of 

 the carapace, and some are more or less distinctly arranged in longi- 

 tudinal rows. The pleural plates of the free thoracic somites are 

 margined with denticles; the dorsal surface is flattened, and on the 

 last three somites the dorso-lateral corner is occupied by a group of 

 denticles, not in a single row. The postero-lateral angles of the last 

 somite are bifid. The abdominal somites carr}" a few denticles, of 

 which the most conspicuous in side view are a dorso-lateral pair on 

 each of the first two somites and on the fifth somite ; the ventro-lateral 

 edges are serrated in the fourth somite. The telson is about twice 

 as long as the last somite; it has about ten pairs of slender lateral 

 spines .and a stronger apical pair. 



The antennular peduncle is dilated distallv, with a terminal brush 

 of seta?. 



The exopod of the uropods is two-thirds as long as the peduncle; 

 the proximal segment of the endopod is much longer than the 



Fig. 75.— Diastyus argentata, male, from the side. 



distal; the spines on the inner ed^e of the endopod are long and 

 feathered. 



Remarks. — The male specimen described above resembles so 

 closely B. fimbnata described by Sars from the South Atlantic (off 

 Cape Frio) that I was at first disposed to identify it wdth that species. 

 Since it differs, however, in possessing an antero-lateral tooth on the 

 carapace and a row of spinules on the side of the pseudorostrum, 

 as well as a bifid postero-lateral tooth on the last thoracic somite 

 and a larger number of lateral spinules on the telson, it seems 

 best, for the present, to record the Cliilian examples under a new 

 name. 



Locality.— Albatross station 2787; off Cliile; lat. 46° 47' 30" S.-, 

 long. 75° 15' 00" W.; 61 fathoms; bottom temperature, 53.9° F.; 

 U.S. N.M. 44028, 44029; many, male and female (including holotype, 

 44029). 



