656 



TELEOSTEI 



CHAP. 



the seas nearly all over the world. But one freshwater form is 

 known, Aphredoderus say anus, the little Pirate Perch of North 

 America, growing to 5 inches in length. The largest marine 

 forms (Beryx and Gephyroberyx) measure from 1 to 2 feet. 



Kecent genera : Beryx, Polymixia, Apkredoderus, Mclampliaes, 

 Plectromus, Scopelogadus, Anoplogaster, Caulolepis, Trachichthys, 

 Paratrachichthys, Gephyroleryx, Myripristis, Holocentrum. 



FIG. 401. Hoplopteryx lewesicnsis. (Restored by A. S. Woodward.) 



Fossil genera : Sphenocephalus, Acrogaster, Pycnosterinx, 

 Hoplopteryx, from the Upper Cretaceous. Asineops, from the 

 Eocene of North America, is supposed to be allied to Apliredo- 

 derus. Beryx is represented by several species in the Upper 

 Cretaceous, and Holocentrum occurs in the Eocene and Miocene. 



Fam. 2. Monocentridae. The single genus Monocentris, 

 with two species, one from the seas of Japan, China, and India, 

 and one from the South Pacific, is very nearly related to the 

 Berycidae, but differs in the absence of ribs on the anterior six 

 vertebrae, in the very large bony scales, forming together a coat 

 of mail, and in the structure of the ventral fin, which is reduced 

 to a strong spine and two or three very short soft rays. The 

 spines of the dorsal fin are very strong and isolated. 



Fam. 3. Pempheridae. The resemblance which the fishes 

 united under this family bear to Beryx is very striking, and 

 applies to the skeleton as well as to the external characters. But 

 the ventral fins are formed of one spine and five soft rays, as 

 in most Acanthopterygians. Bathydupea agrees with Beryx in 



