114 HABITS OF BIRDS. 
fected; and accordingly we often see cagebirds con- 
tent themselves with wetting their heads, without 
touching the rest of the body. They may also be 
frequently seen combing or scratching their heads 
with their claws, no doubt with a similar design. 
This circumstance has given rise to a curious dis- 
cussion concerning the intended use of the claws of 
some species, among which are the nightjar and 
the herons, that are furnished with small teeth like 
a Saw or comb. 


