EUPHAUSIA VALLENTINI 



Euphausia vallentini, Stebbing (Figs. 12-14, 30 i) 



E. vallentini, Stebbing, 1900, p. 545, pi. xxxvii; Holt and Tattersall, 1906, p. 3; Tattersall, 

 1908, p. 13, pi. iv, figs. 4-6; Hansen, 191 1, p. 30; 1913, p. 32, pi. v, figs, i a-f; Zimmer, 

 1914, p. 427; 1915, p. 178; Tattersall, 1924, p. 21 ; Illig, 1930, p. 499; Mackintosh, 1934, 

 p. 76 et seqq.; Hardy and Gunther, 1935, pp. 217-19, fig. 94. 



E. splendens (part), Sars, 1885, p. 80, pi. xiii, figs. 7-17. 



E. patachonica, Colosi, 1917, p. 187, pi. xiv, figs. 11-14, P'- ^v- ^gs- 15-20. 



Description. The carapace is not pro- 

 duced far forwards dorsally. The rostrum 

 is a short sharp triangle about as long as 

 or a little longer than broad; it is much 

 more distinct than that of E. liicens. The 

 anterior margin of the carapace is faintly 

 convex behind each eye (Fig. 12 a). The 

 gastric area of the carapace is moderately 

 or sharply convex. 



The first segment of the antennular 

 peduncle has a very characteristic lobe: 

 it is large, broad and rounded and projects 

 horizontally above the second segment 

 (Fig. 12 a, b). In larger specimens, but 

 not in smaller, there is a small rounded or 

 tooth-like vertical projection on the upper 

 surface of the second segment at the inner 

 distal corner, and a smaller tooth-like pro- 

 jection near the outer distal corner. There 

 is a high dorsal keel on the third segment ; 

 the part seen from the side is strongly 

 rounded above and nearly vertical in front. 



There is a short thin mid-dorsal process 

 from the posterior margin of the third 

 abdominal segment (Fig. 12 f); rarely it is pig. 12. E. vallentini. a, front part of carapace and 

 absent. first segment of antennules from above, x 12. b, left 



The COpulatory organ of the male is very antennular peduncle from the side, X15. c, median 

 similar to that oiE. lucem and E.frigida but ^"'^""^ P™"'' °^ ''^'''^ abdominal segment, x 37. 

 easy to distinguish from them (Fig. 30 h). The proximal process is considerably longer 

 and heavier than the terminal ; its membranous expansions differ in appearance like 

 those of E. hicens, the foremost having striations not possessed by the hindermost, but 

 they are less unequal in size, and the foremost reaches more nearly as far forward as the 

 hindermost; there is a small tooth on the outer side of the distal end of the process 

 between the expansions as in E. lucens. The secondary process or spine on the proximal 



