[4] Besides, we cannot say that there is a want of variety in this music. I may again quote Mr. Barington (Phil. Trans.): "The death of the male parent, just at the time his instructions were required, will occasion some variety in the song of the young ones, who will thus have their attention directed to other birds, which they will imitate or modify according to the conformation of their larynx; and they will thus create new variations, which will afterwards be imitated by their young ones, and become hereditary, until a circumstance of a similar nature may introduce greater variations. If care was taken there need not be two birds that sung exactly alike: however, these varieties are confined within certain limits."--TRANSLATOR. [5] If pine and fir branches cannot be obtained, oak, elm, or beech will do, cut in winter; though not green, yet there will be leaves.--TRANSLATOR. [6] This perhaps depends on the peculiar forms of the bills more than on inclination, for the fauvette and blackcap often attempt to clean their feet without success.--TRANSLATOR. [7] See Rennie's "FACULTIES OF BIRDS," Chap. V., for experiments on the subject.--TRANSLATOR. [8] The reason of this union of vegetable and animal food may be easily seen; the bread supplies the seed for the birds of the first class, and the milk the insects for those of the second, while the third and fourth here find their mixed food; and thus it ought to agree with all. Besides, the birds of the first class do not confine themselves exclusively to seeds; in their wild state they eat many insects, and some even feed their young entirely with them; this proves that animal food is sometimes useful and beneficial to them.--TRANSLATOR. [9] If a rather large, flat, and not very deep vessel be used, in which the birds can bathe at their ease, it will make them more healthy and clean.--TRANSLATOR. [10] White's Selborne, 8vo. edit. 1833. [11] See Rennie's "HABITS OF BIRDS," p. 13.--TRANSL. [12] This, though the common opinion, seems incorrect. See Rennie's "HABITS OF BIRDS," p. 4.--TRANSLATOR. [13] There are varieties in this species: that with the head grey is rare, but when quite white is still more so.--TRANSLATOR. [14] It is rare in Britain.--TRANSLATOR. [15] It is not a native of Britain.--TRANSLATOR. [16] Perhaps from not having been given now and then feathers, the fur and skin of animals, or even beetles, to cleanse the stomach.--TRANSLATOR. [17] It is doubtful as a native of Britain.--TRANSLATOR. [18] The rook, (_Corvus frugilegus_, Linnæus,) seems here to be confounded with the carrion crow. I say nothing about this species, as I have never heard of one being tamed or instructed. It is about the size of the carrion crow, and chiefly differs from it in the base of the beak being naked, and having a rough scabrous skin.--TRANSLATOR.