FLAT-FISHES. 261 
the whole length of the dorsal^ the other that of 
the ventral edge of the body. 
The scales are generally small; those of the 
Flounder, one of which is here represented, have 
the margin entire all round, or only slightly 
waved at the front edge, with no spines behind. 
The form is more or less round, and the appear- 
ance generally much resembles that of a scallop 
shell {Pecten), The concentric lines are coarse, 
and are divided by bands radiating from a point 
SCALE OP FLOUNDER, magnified. 
(a, the natural size.) 
behind the centre, which exhibit only transparent 
crystalline substance, without any trace of lines, 
even under a high magnifying power. 
On the adaptation of the singular structure of 
the Pleuronectidce to their habits, Mr. Yarrell has 
some interesting observations, which we shall 
take the liberty to quote. The Flat-fishes and 
the various species of Skate are, by this depressed 
form of body, admirably adapted to inhabit the 
lowest position, and where they occupy the least 
space, among their kindred fishes. Preferring 
