PLEUKONECTID^. 221 



The fins of the rieuronectidae, at least in several 

 of the species, are semi-spinous, ])ut thia is never so 

 conspicuously the case as to create any douLt about 

 them being true Malacopteiy«fian fishes. 



Like the three preceding families, the flat fish are 

 of very great utility to man, as will at once be seen 

 by turning the eye to the table of species on a 

 preceding page, among which many familiar names 

 will be perceived. 



" The number of species," says Mr. Yarrell, 

 " diminishes as the degrees of northern latitude in- 

 crease. In this country we have sixteen species. '^ 

 At the parallel of Jutland, Denmark, and the 

 islands at the mouth of the Baltic, there are thirteen ; 

 on the coast of Norway they are reduced to ten 

 species ; at Iceland the number is but five, and at 

 Greenland only three." + 



The colours of these fish are remarkable for their 

 uniformity, and in the prevalent tone we at once 

 perceive a benevolent provision for their safety. 

 **■ The resemblance between the colours of the flat- 

 fish, in general, to those of the ground they repose 

 on, is so admirably ordered, as to claim both atten- 

 tion and admiration. The upper surface, or that 

 which is exposed to view and to the action of the 



* This was probably the amount of our native species when 

 the first edition of ]Mr. Yarrcll's work apjieared ; but lie forgets 

 that in the second edition, fi-om which the above extract is 

 taken, he describes two others, so that the total number is 

 eir/hteen. 



+ Britisli Fi.hes, 2d edit. vol. ii. 299. 



