BIRDS 



147 



This suggestion is supported by a comparison between the 

 different species of the genus. Three species are known. If 

 my views are correct, mechanical irritation of the skin of birds, 



Fig. 16. Cephalopterus glabr 

 left, female on the right, 

 and published figures. 



mollis, the Umbrella-bird of Central America, t male on the 

 From specimens in the British Museum of Natural History, 



when excessive, leads to the disappearance of the feathers. 

 Now in C. ornatus, although the caruncle itself is feathered, 

 there is a bare space on the neck at its base, which is covered 



