CLASS TELEOSTEI. 



103 



other fish, twelve or fifteen having been found hanging 

 to a single shark. The pressure of the atmosphere holds 



FIG. 176. 



PIG. 177. 



Echene'is rem'ora. Suck-fish. (|.) 



it so tightly that a strong man can hardly drag it loose. 

 This arrangement probably serves it for cheap and easy 

 transportation, as it is not a good swimmer. 



ORDER DISCOCEPHALI (dis ko sef'a II). 



The Flat-fish is a remarkable illustration among the 

 vertebrates of asymmetry. The young for some time 

 swim vertically, with an eye on each side of the head. 

 Gradually, the parts of head contiguous to one eye are 

 twisted around, 

 till in the adult 

 state the eyes are 

 both on one side, 

 and that always 

 the colored, or up- 

 permost, side, as 

 the fish settles to 

 the bottom ; the 

 opposite side is 

 usually uncolored. The number of species exceeds two 

 hundred, those of the largest size being found in temper- 

 ate and cold regions. The group furnishes important food 

 fish, as the Halibut, Turbot, Sole, and Flounder ; the first 

 sometimes reaching a weight of four hundred pounds. 



Pleu rb ntc' tes pla t?s' sa. Flat-fish. ( T v) 



