His voice, for so small a bird, is a powerful and far-reaching one; and his frequently uttered spring call, or song, composed of two notes repeated two or three times in succession, strikes so sharply on the sense that it compels attention, like ringing blows on an anvil or on the rivets of iron rails and girders, or the sound of sharpening a saw. Saw-sharpener is one of its local names. Another thing--the oxeye is the largest of the tits, consequently the principal member of a group of small birds exhibiting very strongly marked characters. They differ from most small birds, to some extent, in form, colouring, and general appearance, and, in a greater degree, in language and habits. They are extremely active and restless, and spend most of their time in trees, from the bark of the trunk and large branches to the smallest terminal twigs and leaves. In winter, when the elms and other deciduous trees have shed their foliage, and their fine upper boughs appear like a sombre fretwork against the pale sky, the tits are seen at their best; they are then gathered into small flocks or family parties, and may be observed, as they scatter about the tree, clinging to the twigs in every conceivable position, and looking like a company of small sober-coloured paroquets of this cold northern world. They subsist principally on small insects and their eggs, larvæ, and chrysalids, but are almost omnivorous in their diet, feeding on buds, seed, and fruits, and on animal food when it can be had. A meaty bone or a piece of bacon, cooked or raw, or a lump of suet, will quickly attract them, as is well known. The oxeye, pretty little bird as it is, will eat carrion like any crow, and even kill and devour other small birds as big as himself. His rapacious habits have, however, not been very well established. In a captive condition he will occasionally attack a small bird in the same cage, killing it by vigorous blows on the head, and picking out its brains; but in a state of nature the great tit would probably be able to kill only a young or sick bird. For so small a bird he is, undoubtedly, very resolute and strong; the rapid blows of his short, strong bill on the bark sound like those of a nuthatch. Like that bird, he splits open the hard shells of seeds to get at the kernels. The great tit is less social and gregarious than the other species of this group; still, he does unite in small parties, and joins the bands of mixed titmice and other small birds that form so familiar and interesting a feature of woods and copses in autumn and winter.