While the young are being reared, the parent birds frequent corn-fields and meadows, where they search about for those plants which indicate the presence of a grub at the root. Such they unscrupulously uproot, and make a prize of the destroyer concealed beneath. They are much maligned for this practise, but without reason; for, admitting that they kill the plant as well as the grub, it must be borne in mind that several of the grubs on which they feed (cockchafer and daddy-longlegs) live for several years underground, and that, during that period, they would if left undisturbed, have committed great ravages. I have known a large portion of a bed of lettuces destroyed by a single grub of _Melolontha_, having actually traced its passage underground from root to root, and found it devouring the roots of one which appeared as yet unhurt. Clearly, a Rook would have done me a service by uprooting the first lettuce, and capturing its destroyer.
I must here advert to a peculiar characteristic of the Rook which distinguishes it specifically from the Crow. The skin surrounding the base of the bill, and covering the upper part of the throat, is, in the adult birds, denuded of feathers. Connected with this subject many lengthy arguments have been proposed in support of two distinct opinions: one, that the bareness above mentioned is occasioned by the repeated borings of the bird for its food; the other, that the feathers fall off naturally at the first moult, and are never replaced. I am inclined to the latter view, and that for two reasons: first, if it be necessary (and that is not at all clear) that the Rook, in order to supply itself with food, should have no feathers at the base of its bill, I believe that nature would not have resorted to so clumsy a contrivance, and one so annoying to the bird, as that of wearing them away bit by bit: and, secondly, the bare spot is, as far as I have observed, of the same size and shape in all birds, and at all periods of the year, a uniformity which can scarcely be the result of digging in soils of various kinds, and at all seasons. I cannot, therefore, but think that the appearance in question is the result of a law in the natural economy of the bird, that the feathers are not _rubbed_ off, but _fall_ off, and that they are not renewed, because nature never intended that they should grow there permanently; if not, why is there no similar abrasion in the Crow? The number of lambs eaten by Crows is very small after all, and birds' eggs are not always in season, nor is carrion so very abundant; so that, during a great portion of the year, even Crows must dig for their livelihood, and the great distinction between a Crow and a Rook is, that the former has actually no bare space at the base of his bill. But the question is still open, and the reader may make his own observations, which in Natural History, as well as in many other things, are far better than other people's theories.