322 THE COLOUES OF ANIMALS 



the eye. On this green turf flowers and fruit of 

 pretty colour are placed, so as to form an elegant 

 little garden. The greater part of the decoration is 

 collected round the entrance to the nest, and it would 

 appear that the hushand offers there his daily gifts to 

 his wife.' Among the objects — which were always 

 brightly coloured — Dr. Beccari noticed the fruit of 

 Garcinia, like small apples ; the fruits of Gardenias ; 

 the ' beautiful rosy flowers of a splendid new Vaccinium 

 (Agapetesavihli/ornithis);* irnigi, and mottled insects. 

 * As soon as the objects are faded they are moved to 

 the back of the hut.' It is not known whether the 

 female assists the male in making the bower, which 

 is believed to last several seasons. 



I think it may be safely affirmed that the expla- 

 nation of sexual colours as a means of recognition can 

 never account for their aesthetic value, while the ex- 

 istence of an aesthetic sense, to which such characters 

 may appeal, appears to be rendered certain by many 

 observations. 



The hypothesis that sexual colouring is due to a surplus 

 of vitality or is developed in relation to underlying 

 structures 



Mr. Wallace also believes that the appearance of 

 beautiful colours and the growth of plumes and other 



