EEPORT ON THE DEEP-SEA FISHES. 217 



extremely fine and partly free, simple rays, their number corresponding to that of the 

 vertebrae ; each ray starts behind a minute curved spine-like projection of the vertebra 

 (see fig. d'). Anal fin of similar structure, commencing immediately behind the vent, 

 and terminating, like the dorsal, at a short distance from the caudal. Caudal fin very 

 narrow and apparently forked. Ventral fins very narrow, pointed, not quite so long as 

 the head, composed of six very feeble rays ; then- root is about midway between the 

 vent and the head. 



A phosphorescent eye-like organ is situated behind the eye, above the middle of the 

 upper jaw. Similar but smaller organs are disposed along the lower side of the abdomen 

 in a double series, which becomes single behind the ventral fins, and is continued on the 

 tail. About twenty -three may be counted in a series in front of the ventral fins, and 

 seventeen between the ventrals and the vent ; those on the tail become very inconspicuous 

 behind. Another series of minute organs occupies the base of the branchiostegals. 



Colour entii'ely black ; the lateral folds of the dilated portion of the barbel 

 white. 



The number of vertebraj appears to be twenty-two in front of the ventrals, seventeen 

 between the ventrals and the vent, and thirty in the tail. 



Family Salmonid^. 



Argentina, Art. 



The three Atlantic species known are very similar to each other in their organisation, 

 and, therefore, we may infer that they agree very much in their habits. They live at a 

 considerable depth, but probably at some distance from the bottom, as they have never 

 been captured by the dredge or trawl during any of the deeprsea expeditions. 



Argentina silus, Cuv. 



Argentina silus, Collett, Norg. Fisk., p. 173; Nyt Mag. f. Naturvid., vol. xviii., 1884, p. 109. 

 Argentina syrtemium, Goodo and Bean, Proc. U.S, Nat. Mus., vol. i., 1879, p. 261. 



Known chiefly from specimens obtained ofi" the coast of Norway ; Collett reports its 

 occurrence at 80 and 100 fathoms. The specimen described as Argentina syrtensium 

 was taken from the stomach of a Phycis hooked on a line that had been set in 200 fathoms 

 on Sable Island Bank, off" the coast of Nova Scotia. 



(ZOOL. CHALL, EXP. — PAKT LVII. — 1887.) Lll 28 



