THE CUCKOO AND HIS KINDRED. 135 



more astonishing that what little has been noticed 

 or surmised is so widely accepted as unquestionable 

 fact. 



A word on the changes of plumage in the 

 European Cuckoo will bring my few fugitive 

 observations on a most interesting species to a 

 close. I am not aware that these changes of 

 plumage had ever been correctly described, or 

 were at all clearly understood, until Mr. Seebohm 

 and myself worked out the subject from a great 

 number of specimens some ten years ago. There 

 is no difference in colour between the adults of both 

 sexes, this final stage of plumage being reached 

 when the bird is not quite two years old. In 

 this adult plumage the upper parts are slate-gray, 

 suffused with brown on the wings, and becoming 

 nearly black on the tail ; the quills are barred with 

 white on the inner webs, and the tail feathers are 

 tipped with white, and show more or less obscure 

 traces of white bars least conspicuous on the 

 central feathers ; the under parts are grayish-white, 

 darkest on the throat, and barred with dusky-brown 

 below the breast. The bill is black, paler at the 

 base, and with yellow edges ; the orbits, irides, legs 

 and feet are yellow. The young in first plumage 

 have the feathers of the upper parts barred with 



