BIRD LIVERIES AND THEIR MEANING. 37 



the aduh plumage varies from a few "Weeks to 

 about three years or more. Tho?e of my readers 

 who reside in England can watch this process, 

 through a most beautiful series of transitions, 

 in the common starling : the whole process takes 

 in this case but a week or two. 



Changes of colour in plumage may be brought 

 about either by replacing old feathers by new, 

 or by wearing away of c-rtain parts of an adult 

 feather. There is yet a third way, according to 

 some, and this is by an actual deposit of pigment 

 in the feathers in position at the time the re- 

 quired change is made. 



Sometimes colour - changes can be induced 

 artificially, as witness cayenne-fed canaries and 

 birds fed on hempseed. Bulfinches and other 

 birds turn black on a diet of hempseed. The 

 natives of the Amazonian region feed the com- 

 mon green parrot, says Darwin, with the fat of 

 large siluroid fishes, and the birds thus treated 

 become beautifully variegated with red and 

 yellow feathers. In the Malay Archipelago the 

 natives of Gilolo alter, in an analogous manner, 

 the colours of another parrot; so great is the 

 resultant change that the bird has been, after 

 the change, described as a new species. 



Mr Alfred Wallace records an even more 

 remarkable fact. The native South Americans 

 have a curious way of changing the coloration 

 of the plumage of parrots and certain other 

 birds. This they do by plucking out the 

 feathers from the part to be operated upon, and 

 innoculate the fresh wound with the milky secre- 

 tion of a small toad. The feathers then grow of 



