Pareioplitas, or Mailed-cheek Fishes 441 



mon among rocks and algae on the California coast. It is, 

 however, rarely brought into the markets, as it shows great 

 skill in escaping the nets. 



No fossil Hexagrammidce are known. 



The Flatheads or Kochi: Platycephalidae. The family of Pla- 

 tycephalidcz consists of spindle-shaped fishes, with flattened, 

 rough heads and the body covered with small, rough scales. 

 About fifty species occur in the East Indian region, where the 

 larger ones are much valued as food. The most abundant 

 species and usually the largest in size is Platycephalus insidiator, 

 the kochi of the Japanese. The genus Insidiator contains smaller 

 species with larger scales. In all these the head is very much 

 depressed, a feature which separates them from all the Scor- 

 p&nidcz. Hoplichthys langsdorfi, the nezupo or rat-tail of Japan, 

 is the type of a separate family, Hoplichthyida, characterized by 

 a bony armature of rough plates. Bembras japonicus, another 

 little Japanese fish, with the ventrals advanced in position and 

 the skin with rough plates, is the type of the family of 

 Bembradidce. 



The Sculpins: Cottidse. The great family of Cottida or scul- 

 pins is one especially characteristic of the northern seas, where 

 a great variety of species is found. These differ in general 

 from the Scorp&nida, from which they are perhaps derived, 

 in the greater number of vertebras and in the relative feeble- 

 ness or degeneration of the spinous dorsal, the ventrals, and 

 the scales. In all these regards great variation exists. In 

 the most primitive genus, Jordania, the body is well scaled, 

 the spinous dorsal well developed, and the ventral rays 1,5. In 

 Hemitripterus a large number of dorsal spines remains, but the 

 structure in other regards is highly modified. In the most 

 degraded types, Cottunculus, Psychrolutes, Gilbertidia, which 

 are also among the most specialized, there is little trace of 

 spinous dorsal, the scales are wholly lost, and the ventral fin 

 is incomplete. Most of the species of Cottida live on the bot- 

 tom in shallow seas. Some are found in deep water and a few 

 swarm in the rivers. All are arctic or subarctic, none being 

 found to the south of Italy, Virginia, California, and Japan. 

 None are valued as food, being coarse and tough. Scarcely 

 any are found fossil. 



