614 



TELEOSTEI 



definite one, and it has been used for the division of these Fishes 

 into genera or sub-genera. 1 The ventral fins have a more forward 

 position than in most other members of the Family. 



Fam. 7. Alepidosauridae. Characters as in the preceding, 

 but supratemporal simple, attached to the opisthotic, and dorsal 

 fin very long, formed of slender, non-articulated, simple or bifid 

 rays, extending along nearly the whole length of the back, 

 followed by a small adipose fin. The air-bladder is absent and 

 the body scaleless. The skeleton is feebly ossified ; the dentition 

 is very powerful, some of the teeth on the palate and mandible 

 being very strongly enlarged. 4 or 5 species are known, from 

 considerable depths in the Atlantic and Pacific Oceans, referable 

 to one genus, Alepidosaurus or Plagyodus. A. ferox, from the 

 Atlantic, reaches a length of 4 feet. 



FIG. 372. Alepidosaurus ferox, i nat. size. (After Goode and Bean.) 



Fam. 8. Cetomimidae. The affinities of the recently dis- 

 covered genera Hondeletia and Cetomimus, deep-sea Fishes from 

 the North Atlantic, at depths of 1000 to 1600 fathoms, are still 

 uncertain, as the skeleton could not be examined ; they are 

 probably most nearly related to the Scopelidae. The head is 

 enormous, with very wide gape, that of Cetomimus being 

 suggestive of that of a Right Whale ; the teeth are small and 

 coarsely granular ; the gill-openings are very wide; the body is more 

 or less compressed and scaleless ; the dorsal and anal fins are 

 opposed to each other ; no adipose dorsal fin. In Rondeletia, the 

 eyes are moderately large, and ventral fins, with 5 rays, are present; 

 in Cetomimus, the eyes are very small, and ventral fins are absent. 



1 Of. Raffaele, Mitth. Zool. Stat. Neap. ix. 1889, p. 179; Liitken, " Spolia 

 Atlantica," ii. 1892 ; Goode and Bean, " Ocean. Ichthyol." p. 70 (1895). 



