PISHES. 339 



Labrus (L. pavo), described,™ with pardonable exaggeration, as 

 formed of pollslied scales of gold, encrusting lapis-lazuli, rubies, 

 sapphires, emeralds, and amethysts — we may, with much prob- 

 ability, accept this belief; for we have seen that the sexes in 

 at least one species of the genus differ greatly in color. With some 

 fishes, as with many of the lowest animals, splendid colors may 

 be the direct result of the nature of their tissues and of the sur- 

 rounding conditions, without the aid of selection of any kind. 

 The gold-fish (Cyprinus auratus), judging from the analogy of the 

 golden variety of the common carp, is perhaps a case in point, 

 as it may owe its splendid colors to a single abrupt variation, 

 due to the conditions to which this fish has been subjected under 

 confinement. It is, however, more probable that these colors 

 have been intensified through artificial selection, as this species 

 has been carefully bred in China from a remote period.^ Under 

 natural conditions it does not seem probable that beings so highly 

 organized as fishes, and which live under such complex rela- 

 tions, should become brilliantly colored without suffering some 

 evil or receiving some benefit from so great a change, and con- 

 sequently without the intervention of natural selection. 



What, then, are we to conclude in regard to the many fishes, 

 both sexes of which are splendidly colored? Mr. Wallace" be- 

 lieves that the species which frequent reefs, where corals and 

 other brightly-colored organisms abound, are brightly colored in 

 order to escape detection 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-colored 

 corals or other organisms for the fishes to resemble; yet many 

 species in the Amazons are beautifully colored, and many of the 

 carnivorous Cyprinidse in India are ornamented with "bright 

 "longitudinal lines of various tints."'^ Mr. M'Clelland, in de- 

 scribing these fishes, goes so far as to suppose that "the peculiar 



" Bory de Saint Vincent, in 'Diet. Class. d'Hist. Nat.' torn. ix. 1826, 

 p. 151. 



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

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

 nese Notes and Queries,' Aug. 1868, p. 123) has searched the ancient 

 Chinese encyclopedias. He finds that gold-flsh were first reared in con- 

 finement 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 Hangchow a variety 

 "called the fire-flsh, from its intensely red color. It is universally ad- 

 "mired, and there is not a household where it is not cultivated, in 

 "rivalry as to its color, and as a source of profit." 



»» 'Westminster Review,' July, 1867, p. 7. 



=1 'Indian Cyprinidae,' by Mr. J. M'Clelland, 'Asiatic Researches,' vol. 

 xix. part ii. 1839, p. 230. 



