408 Animal Life and Intelligence. 



preferences have arisen in association with the flowers from 

 which the bees obtain their nectar. They have a practical 

 basis of biological value. But there seems no doubt that 

 certain colours are now for them more attractive than 

 others. Bees and other insects are, undoubtedly, attracted 

 by flowers ; these flowers excite in us an esthetic pleasure ; 

 the bees are, therefore, supposed to be attracted to the 

 flowers through their possession of an aesthetic sense. 

 Now, this does not necessarily follow. It is the nectar, not 

 the beauty of the flower, that attracts the bee. So long as 

 the flower is sufficiently conspicuous to be rapidly distin- 

 guished by the insect, the conditions of the case are met 

 so far as insect psychology is concerned. The fact remains, 

 however, that the flowers thus conspicuous to the insect 

 are fraught with beauty for us. 



In the case of sexual selection among birds, again, I 

 believe that the gorgeous plumage has its basis of origin in 

 that pre-eminent vitality which Mr. Tylor and Mr. Wallace 

 have insisted on. But, as before indicated, this will not 

 serve to explain its special character for each several species 

 of birds. Here, again, conspicuousness and recognition 

 are unquestionably factors. But that the bright plumage 

 of male birds awakens emotional states in the hens, that it 

 probably also arouses sexual appetence, seems to be shown 

 by the manner in which the finery is displayed by the 

 male before the female. I think it is probable, also, that 

 pleasure, becoming thus associated with bright colours in 

 the mate, is also aroused by bright colours in other asso- 

 ciations. Thus the gardener bower-bird, described by Dr. 

 Beccari,* collects in front of its bower flowers and fruits of 

 bright and varied colours. It removes everything unsightly, 

 and strews the ground with moss, among which it places 

 the bright objects from among which the cock bird is said 

 to select daily gifts for his mate's acceptance ! Dr. Gould 

 states that certain humming-birds decorate their nests 

 "with the utmost taste," weaving into their structure 

 beautiful pieces of flat lichen. If by crediting birds with 



* Nature, vol. xl. p. 327. 



