Heads and Necks 263 



The Laughing Thrush of the Himalaya Mountains 

 has every feather upon its head lengthened and perma- 

 nently erect, forming a soft, spreading halo. 



Fig. 205. — Hooded Merganser. (From a photograph provided by the American 

 Museum of Natural History.) 



In almost every Family of birds we find certain spe- 

 cies with long, well-developed crests. Among the ducks, 

 the Hooded Merganser has a compressed, semicircular 

 halo of delicate feathers, while the Mandarin Duck has 

 a broad, many-coloured, erectile crown, which is con- 



