FOREHEAD OF THE ROOK. 51 



I request the reader to bear in mind, that these 

 arguments are brought forward only under the ac- 

 cepted supposition of naturalists, that the feathers 

 are removed by the process of the bird thrusting its 

 bill into the ground. But he who examines the 

 subject with attention will at once see that the 

 process itself could not destroy the feathers on the 

 head of the rook ; because, if they were destroyed 

 by this process, the carrion crow, the jackdaw, the 

 jay, the magpie, and the starling would all exhibit a 

 similar nudity on the forehead, and at the base of 

 the bill ; for they all thrust their bills into the 

 ground proportionably as deep as the rooks do 

 theirs, when in quest of worms and grubs. More- 

 over, if the feathers are eradicated by the act of 

 thrusting the bill into the ground, they would be 

 succeeded by new ones, during the time in which 

 that act could not be put in execution ; for example, 

 during a very dry summer, or during a very hard 

 winter ; and at these periods, as no action on the 

 part of the rook would operate to destroy the coming 

 feathers, an evident change would soon be observed 

 about the head of the bird. In 1814, the ground 

 was so very hard frozen, and covered with snow for 

 some months, that the rooks could not by any 

 means have an opportunity of thrusting their bills 

 into it. Still, during this protracted period of frost, 

 I could not see a solitary instance of renewal of 

 the feathers on the forehead, or at the base of the 

 bill, in the many birds which I examined. 



I deny that the rook does, in general, thrust his 



E2 



