Chap. XII. FISHES. 17 



period.^^ Uii'ler natural conditions it does not seem 

 probable that beings so higlily organised as fishes, and 

 which live under such complex relations, should become 

 brilliantly coloured without suffering some evil or re- 

 ceiving some benefit from so great a change, and conse- 

 quently without the intervention of natural selection. 



What, then, must we conclude in regard to the many 

 fishes, both sexes of which are splemlidly coloured? 

 Mr. Wallace^' believes that the species which frequent 

 reefs, where corals and other brightly-coloured organisms 

 abound, are brightly coloured in order to escape detec- 

 tion by their enemies ; but according to my recollection 

 they were thus rendered highly conspicuous. In the 

 fresh-waters of the Tropics there are no brilliantly- 

 coloured corals or other organisms for the fishes to 

 resemble ; yet many species in the Amazons are beau- 

 tifully coloured, and many of the carnivorous Cypri- 

 nidae in India are ornamented with '* bright longitu- 

 " dinal lines of various tints." ^^ Mr. M'Clelland, in 

 describing these fishes goes so far as to suppose that 

 " the peculiar brilliancy of their colours " serves as " a 

 " better mark for king-fishers, terns, and other birds 

 " which are destined to keep the number of these fishes 

 " in check ; " but at the present day few naturalists will 



^ Owing to some remarks on this subject, made in my work ' On the 

 Variation of Animals under Domestication,' Mr. W. F, Mayers 

 (' Chinese Notes and Queries,' Aug. 1868, p. 123) has searched the 

 ancieut Chinese encyclopedias. He finds that gold-fish were first 

 reared in confinement during the Sung Dynasty, which commenced 

 A.D. 960. In the year 1129 these fishes abounded. In another place 

 it is said that since the year 1548 there has been " produced at Hang- 

 " chow a variety called the fire-fish, from its intensely red colour. It 



" is universally admired, and there is not a household where it is not 



" cultivated, in rivalry as to its colour, and as a source of profit." /r^'TT^ 

 '7 'Westminster Etview,' July, 1867, p. 7. /O^^ ' ' 



28 "Indian Cyprinida3," by Mr. J. M'Clellaud, « As-atic EeseaW^j'^O^i 

 vol. xix. part ii. 1839, p. 230. /C> O 



VOL. II. C/QO ^ 



