﻿40 ON THE CLASSIFICATION OF BIRDS. 



has a little crest just above the nostrils, while in the 

 Cyanurus cristatellus {fig. 18.) this form is at its max- 

 imum of development. Now, it is quite obvious that 

 this is not a crest which admits of being raised and 

 depressed at pleasure ; for 

 the feathers are so much 

 curled that they could not 

 repose flat upon the others, 

 as in ordinary crests ; and 

 this result will be much 

 more apparent on looking 

 to the last-named bird. 

 The next modification is 

 when the frontal feathers 

 are much longer than those 

 on the crown, and form a sharp elevated ridge immedi- 

 ately before the eye, without being continued further : 

 this, in fact, is but a half crest, and is possessed by very 

 few birds, among which Metopia galeata Sw.*, a beau- 

 tiful manakin of Brazil, is the most remarkable. Some 

 approach is also made to this structure in two other 

 splendid little species of the same group — Pipra pareola 

 and Pipra caudata f ; but their crests are rather rudi- 

 mentary. In the third form we see the compressed 

 crest in its full development : not only the frontal 

 feathers, but the whole of those on the crown are com- 

 pressed together so as to be quite compact, and an 

 elevated curve overarches the entire head. Those beau- 

 tiful birds, the Rupicola Cayana of South America, and 

 the Calyptomina viridis of India, afford us striking ex- 

 amples of this structure ; where the frontal feathers are 

 so long, and so much pointed forward, as to exceed, and 

 in part conceal, the bill of the bird. The great crowned 

 pigeon of India, gives us likewise a notable and mag- 

 nificent illustration of this description of crest, except 

 that the peculiar loose texture of the feathers takes 

 from it that compactness, and carinated edge, which are 

 so remarkable in the birds just before mentioned. This 



* Brazilian Birds, vol. i. pi. 23. f Ibid. pi. 45, 46. 



