OB, PLAIN TEACHING. 



87 



351. 



of the head. One side of the fish 

 is white, the other dark. The 

 former is commonly mistaken for 

 the belly of the fish, the latter for 

 its back ; but, in fact, the bach, 

 15, is that along which the dorsal 

 fin, extends ; the belly, 16, being 

 denoted by the ventral fin. Fishes 

 of this family swim on their sides, 

 and inhabit muddy or sandy beds, 

 where, their dark sides being up- 

 permost, and in colour blending 

 with that of the bed on which 

 they lie, it is difficult to perceive 

 them. Here they lie, looking 

 upward, watching for their prey, 

 "When, suddenly alarmed, they 

 seek to escape, they turn their 

 true backs, 15, upward, and dart 

 through the water, presenting the 

 curious appearance of fishes dark 



on one side, and silvery white on 

 the other. The right side of the 

 sole is usually dark, the left white. 

 But curious exceptions are met 

 with, in which this order is re- 

 versed ; and Mr. Tarrell found a 

 curious specimen dark on both 

 sides. 



The turbot {Rhombus maxi- 



18 



Sri. 



mus), 18, differs from the sole, 



