THE FLAT-FISH. 235 



into elegant contortions and undulations ; often it hangs nearly 

 perpendicular with the tail near the surface ; now and then it 

 butts against the side of the vessel with reiterated blows of its 

 nose, as if it could not make out why it should not go forward 

 where it can see no impediment. Now it twists about as if it 

 would tie its body into a love knot, then hangs motionless in 

 some one of the ' lines of beauty ' in which it has accidentally 

 paused." 



The family of the Pleuronectida? or Flat-fishes recommends 

 itself to our notice as much by the singularity of its form as by 

 its usefulness to man. " The want of symmetry," says Yarrell, 

 " eo unusual in vertebrated animals, is the most striking and 

 distinctive character of these fishes: the twisted head with both 

 eyes on the same side, one higher than the other, not in the 

 same vertical line, and often unequal in size ; the mouth cleft 

 awry, and the frequent want of uniformity in those fins that 

 are in pairs, the pectoral and ventral fins of the under side 

 being generally smaller ; and the whole of the colour of the 

 fish confined to one side, while the other side remains white, 

 produce a grotesque appearance : yet a little consideration will 

 prove that these various and seemingly obvious anomalies are 

 perfectly in harmony with that station in nature which an 

 animal possessing such conformation is appointed to fill. 



" As birds are seen to occupy very different situations, some 

 obtaining their food on the ground, others on trees, and not a 

 few at various degrees of elevation in the air, so are fishes 

 destined to reside in different depths of water. The flat-fishes 

 and the various species of skate are, by their depressed form of 

 body, admirably adapted to inhabit the lowest position, where 

 they occupy the least space among their kindred fishes." 



" Preferring sandy or muddy shores, the place of the flat- 

 fish is close to the ground ; where, hiding their bodies horizon- 

 tally in the loose soil at the bottom, with the head only slightly 

 elevated, an eye on the under side of the head would be use- 

 less ; but as both eyes are placed on the upper surface, an 

 extensive range of view is afforded in those various directions 

 in which they may either endeavour to find suitable food or 

 avoid dangerous enemies. Light, one great cause of colour, 

 strikes on the upper surface only ; the under surface, like that 

 of most other fishes, remains perfectly colourless. Having 



