FLAT-SIDED AND FLAT-BACKED FISHES 399 



said, was once frying a flat fish, but just as one side was done 

 the oil in the pan dried up and no more was available. A 

 practical man would have eaten the cooked side and left the 

 raw portion for further consideration ; but Moses, greatly irri- 

 tated, cast the half-fried fish into the sea. The creature came 

 to life, and ever since that day has been brown on one side and 

 white on the other. Notwithstanding the above narrative, let 

 it be confessed that there are fish which I may term ' done on 

 both sides ' that is to say, though true flat fish, for some reason 

 or other they have developed colour on both sides ; but these 

 are rare. They are, however, said to be better eating than the 

 parti-coloured flat fish. Disregarding the Egyptian legend, it 

 would seem that the colouring on one side of the flat fish is a 

 provision of nature by which the fish, assimilating itself to the 

 appearance of the ground on which it lies, or in which it buries 

 itself, is not easily seen by its enemies. In foreign seas there 

 are certain flat fish which are found among coral reefs, and 

 these are ornamented with rather striking colours. 



I have called these flat fish remarkable freaks of nature 

 because, when hatched, they are coloured on both sides alike 

 and swim back upwards like any ordinary fish. Being very 

 thin from side to side and very deep from back to belly, in the' 

 course of a week or two they begin to topple over and swim 

 on their side. Then follows a marvel. The eye which regards 

 the bottom of the sea soon wearies of the prospect and gradu- 

 ally moves until it reaches the uppermost side, where it remains 

 for the rest of the fish's life. This remarkable phenomenon was 

 observed many years ago. How such an extraordinary change 

 of appearance takes place has been a subject of considerable 

 difference of opinion among naturalists. Some have said that 

 the eye works round under the skin and by the snout, others 

 that it passes under the frontal or forehead bone of the fish 

 right through to the other side, and some that it actually cuts 



