568 Mr. G. L. Bates on the Breeding-Seasons 



The Thrushes. — Tardus saturatus has breeding-birds, or 

 nests with eggs, at all seasons, but with a decided preference 

 for the rainy months. In the drier of the two dry seasons 

 no nests were found, and two out of three birds examined 

 were not breeding. Neocossyphus poensis furnishes breeding- 

 birds in every season except the drier dry season, aud in 

 this case a good many birds were examined in that season 

 and found not breeding. Exactly the same thing is true of 

 Cossypha cyanocampter, and of the two species of Alethe. 

 Callene shews breeding-birds in all the seasons, and so do 

 the three common species of Turdinus. Of all the birds 

 here mentioned under the " Thrushes," except Tardus itself, 

 great numbers were caught in snares on the ground, and 

 many observations were recorded. 



Seasonal Changes of Plumage and Moulting. 



Of no bird that is a resident of Southern Kamerun and 

 breeds there, excepting the two or three already noticed 

 belonging to the Spermestine division of the Weavers, do I 

 know that it has a " winter plumage" — that is, that having 

 once changed from the plumage of the immature bird to 

 that of the adult, it again assumes a plainer plumage, or one 

 resembling that of youth. When the males of Hyphantornis 

 cucullatus, to take the most familiar instance, have assumed 

 their bright yellow and black colours, they seem to keep 

 them for the rest of their lives. This is in accordance with 

 the fact already stated, that when adult they always have 

 the breeding-organs large. 



I have looked up several facts from my note-books 

 regarding the Sun-birds in particular, which all tend to 

 shew that when the males have once assumed the bright 

 metallic colours, they never lose them again. 



(1) Examples of birds changing from the plain to the 

 metallic or velvety plumage have been noted in the cases 

 of Cinnyris superba, C. chloropygia, and Chalcomitra 

 angolensis. But an example has never been noted in which 

 the change is from the metallic or velvety into the plain 

 plumage. I have particularly attended to this point. 



