2856 THE BONY FISHES AND GANOIDS 



Measuring rrom twelve to eighteen inches in length, this fish seems to be partly 

 pelagic and partly littoral in its habits; being found in New Zealand, where it is 

 known as the sand eel, in bays with a sandy bottom, while elsewhere it has been 

 taken in the open sea. In New Zealand its flesh forms an article of food. The 

 family is also represented by an extinct genus (Notogoneus} from the Eocene of the 

 United States. 



THE SCOPKLOIDS Family SCOPELID& 



As an example of an important family of, for the most part, pelagic or deep- 

 sea fishes, we select the so-called phosphorescent sardine, Scopelus cngraulis, as be- 

 ing a member of the typical genus. The members of this family agree with the 

 last in having the parietal bones united and no true tail vertebra, but they may be 

 distinguished externally by the absence of barbels and the presence of a small fatty 

 fin some distance behind the dorsal, and likewise by the want of spines on the 

 scales, when the latter are present; some genera having the body scaled, while in 

 others it is naked. The margin of the upper jaw is always constituted solely by the 

 premaxillae; the gill cover may be incompletely developed; the gill opening is wide; 

 false gills are present; but an air bladder is wanting. The intestine is remarkable 

 for its shortness; and the eggs are inclosed in the sacs of the ovaries, whence they 

 are extruded by means of ducts. Containing a large number of existing genera, 

 the family is likewise represented by several extinct types, the earliest of which 

 dates from the Cretaceous of Istria. 



In the typical genus the body is oblong in form and more or less markedly 

 compressed, with the investing scales of large size. Along the sides run series of 

 phosphorescent spots; while similar grandular structures may in some species occur 

 on the front of the body and on the back of the tail. The cleft of the mouth is un- 

 usually wide; the premaxillary bones being long, slender, and tapering, and the max- 

 illae well developed. The teeth are villiform, and the eye is relatively large. The 

 pelvic fins are inserted just in front of or immediately below the line of the foremost 

 rays of the dorsal (which is situated nearly in the middle of the length of the body), 

 and are composed of eight rays; the fatty fin is very small; and the anal is generally 

 long; and the caudal forked. There are from eight to ten rays in the branchioste- 

 gal membrane. Dr. Giinther writes that "the fishes of this genus are small, of 

 truly pelagic habits, and distributed over all the temperate and tropical seas; they 

 are so numerous that the surface net, when used during a night of moderate 

 weather, scarcely ever fails to inclose some specimens. They come to the surface 

 at night only; during the day, and in very rough weather, they descend to depths 

 where they are safe from sunlight or the agitation of the water. Some species 

 never rise to the surface; indeed, scopeli have been brought up in the dredge from 

 almost any depth to two thousand five hundred fathoms." Upward of thirty 

 species of this genus are known, and there is also an allied genus (Gymnoscopelus) 

 distinguished by the absence of scales. 



Among several other remarkable forms of the family, we may especially notice 

 a very curious fish {Ipnops} obtained at great depths during the voyage of the Chal- 



