CH.VI.] BARENESS AT BASE OF ROOK'S BILL. 217 



amongst naturalists, as to whether the bareness 

 of the Rook's bill is, as Bewick says, " an original 

 peculiarity/' or whether the feathers which at first 

 grow on its base are worn off by contact with the 

 soil into which it is constantly thrust. It seems to 

 me that those who hold the former theory have 

 the best of the argument, but as the only way of 

 proving which is in the right would be to confine 

 rooks from their infancy in a place where they 

 could not possibly have access to mould, or other 

 substance by which the bill-feathers could be 

 rubbed off, it will probably be some time before 

 the question is solved. Yarrell mentions that 

 "two or three other birds (not British) are now 

 known to exhibit this peculiarity of losing the 

 bill-feathers," but we might go nearer home for a 

 case, in which something analogous occurs, that 

 of babies, on whose foreheads at their birth is 

 visible a distinct down, which shortly afterwards 

 disappears. Nor is this peculiarity noticeable only 

 in babies : every one must have observed how much 

 more woolly the heads of young asses are than 

 those of older ones, and Sir J. Emerson Tennent in 

 his interesting Work on Ceylon (Vol. n. p. 385, 

 note) similarly remarks that, " the young elephants, 

 when captured, are frequently covered with a 



