BIRDS OF ETHIOPIA AND KENYA COLONY 



411 



on the degree of abrasion of the plumage of full-grown birds with 

 smooth tomia, as it is not possible to tell the age of the bird after it 

 has attained its full size except by the bill. With wear, the light 

 edges of the upper wing coverts gradually disappear and the feathers 

 of the chin and throat fade laterally, leaving the median portion 

 darker, thereby causing the effect of dark shaft stripes. The post- 

 juvenal molt appears to be complete; that is, all the specimens 

 that are molting remiges or rectrices are also molting body feathers, 

 and none with worn wing and tail feathers are clad in fresh body 

 plumage. The next plumage is the first adult plumage, which is like 

 every subsequent one, the only seasonal differences being due to 

 abrasion. Adults appear to breed in fairly fresh plumage, not in 

 worn plumage as in so many other birds. Here again, as in Lopho- 

 ceros deckeni the explanation seems to be that the postnuptial molt 

 is a prolonged one, and that the next breeding season begins before 

 the plumage has had much chance to become abraded. 



The wing molt in this species appears to be somewhat irregular, 

 and the tail molt to begin with the middle rectrices and proceed 

 outward. 



The size variations of the nominate form may be judged from the 

 following figures : 



