14 W. M. TATTEKSALL. 



of the antennule of the ' Challenger ' specimen and (Plate IV., Fig. 4) a sketch of 

 the antennule of one of the ' Discovery ' examples for comparison with those given 

 by Stebbing (1900). This shows clearly, in my opinion, that all three specimens 

 belong to one species, and that the absence of the spine on the third pleon segment 

 of the ' Challenger ' example is the result of accident or possibly an abnormality. 

 The peculiar shape of the antennular lobe is practically the same in the ' Discovery ' 

 and ' Challenger ' individuals, and only differs from Stebbing's types in degree, a 

 result of more complete growth. 



The rostrum of E. vallentini is very like that of E. splendens, G-. 0. Sars, but is 

 slightly longer, and the angle formed by its margins a little more acute. Sars may 

 have been misled by the resemblance between the rostra of the two species, which 

 caused him to overlook the marked differences which exist in the antennulse. Dr. 

 Hansen has seen the ' Challenger ' specimen referred to, and agrees with my 

 interpretation of its specific identity. 



One of the ' Discovery ' E. vallentini is a male, but unfortunately the copulatory 

 apparatus on the first pleopods is considerably damaged, so that I am obliged to refer 

 to the ' Challenger ' example, which is likewise an adult male, for a description and 

 figure of this apparatus (Plate IV., Fig. 6). The figure represents the inner lobe of 

 the endopodite of the first pleopod of the male. This inner lobe bears internally two 

 movable processes, the inner and more distal of which is feebly curved, slightly over- 

 reaching the inner lobe and bifid at the tip. The external and more proximal of the 

 two processes has the distal extremity greatly expanded, the expansion very much 

 broader than long, oblique, and divided into two lobes, the more distal of which is the 

 larger. On the under side of the expansion of the proximal process as viewed in the 

 figure there is a small spine-like process. The inner lobe of the endopodite itself bears 

 a strongly curved uncinus with a small secondary spine near the tip. 



Distribution. — Southern Pacific, between New Zealand and Chili (' Challenger ') ; 

 Falkland Islands {Stebbing). 



EUPHAUSIA, sp. 



Locality of capture. — Lat. 57° 25' 30" S., long. 151° 43' E., nineteen specimens, 

 10-18 mm. 



On first looking over these specimens I identified them with Euphausia splendens, 

 G. 0. Sars (1885), a species which Hansen (1905 (2)) considers to be different from 

 E. splendens, Dana, and which he has re-named E. lucens. Hansen, in the same 

 paper, notes that E. splendens, G. 0. Sars, has the first joint of the antennular 

 peduncle without a leaflet, but distally produced above. Holt and Tattersall (1906 

 (1)) have confirmed this statement by an examination of Sars' type specimens of E. 

 splendens, in which they found that in the female type the lobe is quite conspicuous 

 both in lateral and dorsal view ; while in the male type, which is considerably smaller 

 than the female, the lobe is less developed, but still easily seen in lateral view. Sars 



