PERCHING BIRDS. 133 
Their partiality for the grub of the cockchafer is pro- 
ductive of the most beneficial results. But I have seen 
long patches of sward in the forests and parks so 
thoronghly and uniformly dug up in their search for 
them that it was greensward no longer; not a patch as 
Jarge as the hand had escaped being uprooted, clearly 
showing the abundance of these destructive larvee. 
I do not agree with the opinion so commonly ex- 
pressed, that the bare space around the base of the bill 
of the rook is produced by its habit of grubbing in the 
ground; I have watched them very closely when they 
have been engaged in upturning the turf as I have 
described, and never saw the bill plunged beyond its 
length. Even when they are searching the newly- 
ploughed ground, I never observed any action which 
could produce the abraded appearance. I admit it is 
very natural to attribute it to such a cause; but is it 
not a singular fact, telling strongly against this theory, 
that in the extent of this bare skin there should be no 
appreciable difference in one bird over another, but all 
are equally denuded? Surely, if it was produced by 
digging, some variation in this would be noticeable, but 
I never saw such; the jackdaw, too, is as great a digger 
as the rook, and bed a shorter bill, and yet the base is 
clothed with feathers which bear no trace of injury from 
such a cause. The editor of The Field favoured me 
with the following note on this point :—‘‘There was a 
long discussion on this subject in The Field some years 
since, and several instances were mentioned in which 
rooks kept in confinement, where they could not dig, 
nevertheless lost the feathers. We also received the 
head of a rook in which the feathers were only partially 
removed ; and those which yet remained were nearest 
