I90 THE COURTSHIP OF ANIMALS 



the nature of their coloration. Such, for example, as 

 the marine types of birds. 



The metallic and iridescent tints to which reference has 

 just been made, occur among animals to which they can be 

 of but doubtful value, as in the Golden Mole, for example, 

 or the inside of the Oyster shell. Their existence in such 

 places well illustrates what we may call the fortuitous, 

 or apparently fortuitous, beginning of colour of whatever 

 kind, regarded from an analytical point of view. That 

 is to say, we are not concerned with the fact that animals 

 are coloured — that is inseparable from their existence ; but 

 with why this coloration should, in some cases, assume 

 so conspicuous a brilliancy and vividness — a coloration 

 varying in its character with every species, but apparently 

 unchanging among the individuals of that species. 



No answer to this, likely to find general acceptance, 

 seems to be forthcoming at present. But it is significant 

 to remark that all coloration of the kind now under con- 

 sideration has its origin, as have most other structural 

 characters, in the male. It is as true of coloration as of, 

 say, skeletal characters. One turns to the male for 

 what is new in the history of a species, to the female and 

 young for indications of past history. It is equally 

 true that in their coloration one finds the same sequence 

 of development — the male first, then the female, then 

 the young, till both sexes, and all stages, are once more 

 alike in hue. And this rule seems to apply to coloration 

 of all kinds — Protective — Warning — Epigamic. 



The tendency to develop brilliant colours is associated 

 with some physiological diathesis with which we are not 

 yet acquainted. But once having started, this tendency 

 gathers force with each succeeding generation and con- 

 tinues to exhibit an almost kaleidoscopic capacity for 



