60 OIL GLANDS OF BIRDS. 



ON BIRDS USING OIL FROM GLANDS FOR 

 THE PURPOSE OF LUBRICATING THE SUR- 

 FACE OF THEIR PLUMAGE." 



" Nardo perunctus." Nor. Epod. 



BIRDS, in general, are much troubled with vermin. 

 After applying the solution of corrosive sublimate 

 in alcohol to the fresh skin of a bird, you will see 

 an amazing quantity of insects coming out from all 

 parts of the plumage, but especially from the head. 

 They linger for a few hours on the extremities of 

 the feathers, and then fall off and die : they are of 

 all sizes, from the full-grown insect down to the mi- 

 nutest little creature which has just entered into 

 life and motion. No part of the body of the bird 

 is exempt from their annoyance ; and we may judge 

 how much the birds suffer from it, by their perpe- 

 tual attempts to free themselves from the tormenting 

 attacks of the insects. 



People are apt to suppose that a bird is preening, 

 or rectifying, its feathers, when they see it applying 

 its bill to the plumage, and running it down a fea- 

 ther, from the root to the extremity: but a man 

 well versed in the habits of birds knows, when he 

 sees the bird do this (except after it has got wet), 

 that it is trying to dislodge the vermin, which cling 

 with an astonishing pertinacity to the feathers. 

 Now, while the bird is thus employed on that part 

 of its body just above the tail, where there is a 

 gland, some people imagine that the bird is pro- 



