Finally, a word or two about the "game-birds." These are all birds easily distinguished by reason of their short, rounded, deeply convex wings, which, driven with incredible speed, produce a "whirring" sound--very pleasant to the ears of the sportsman. The flight is never continued very far. The English partridge may be distinguished by the horse-shoe mark on the breast: the French partridge by the beautiful pearl-grey colour of the flanks, relieved by short bars of black, and chestnut-red, and red legs and beak. It is also known, indeed, as the "red-legged" partridge. The pheasant is a far larger bird, with a long, pointed tail. The grouse is confined to moors. His heavy build and red coloration distinguish him at once. The black-cock is a still larger bird; the male with a wonderful metallic, steel-blue plumage, and lyrate tail. His mate--the "grey-hen"--is chestnut brown, barred with black. The capercailzie is the largest of all, almost rivalling a turkey. His size alone suffices to distinguish him. Moreover, only a very few can enjoy the pleasure of gazing at him, for he confines himself to the coniferous woods of Scotland. [Illustration: Buzzard Soaring.] CHAPTER VIII. The Wings of Nestling Birds. "The blue eggs in the Robin's nest Will soon have wings, and beak, and breast, And flutter and fly away."--_Longfellow._ The wing of the unhatched bird--Of the coots and water-hen--The Hoatzin's wings--The wing of Archæopteryx--Moulting--The nestling game-birds and ducks--Teaching the young to fly. At first sight it may seem a little strange to introduce nestlings into a book devoted to birds in flight. But there are aspects of the wing of nestling birds which must, indeed, be borne in mind when considering the wing of the adult. It was pointed out, in Chapter I, that the wing of the adult had but three fingers and two wrist-bones. This condition represents the last stage in the evolution of the Avian wing. The wing of the nestling gives a clue to an earlier stage in its history. But we can get even further back than this. For if we examine the wing of an unhatched bird, we shall be able to get still nearer to the birth, and growth of the wing out of a reptilian fore-limb. Here as many as six wrist-bones may be found. And the "palm-bones," which in the adult are welded together, are here quite separate. This stage, then, carries us back towards the ancestral, reptilian, fore-limb used for walking, or perhaps for climbing. And there is another sign of this earlier, reptilian, period to be found in such a wing. At the tip of the thumb and first-finger, in unhatched ducks, game-birds, and water-hens, for example, you will find a small claw. By hatching-time the claw of the first finger will have disappeared, but it is still retained in the case of the duck and the water-hen. In the adults of all three you will rarely find more than the claw of the thumb: and this now serves no useful purpose whatever.