Now, when the young birds are taken from the nest and reared by hand, they insist for a long time on being fed in the juvenile manner. However, by and by they begin of their own volition to pick up food after the manner of the adults. At first they are very clumsy about it, but they persevere until they acquire skill, and presently they refuse entirely to open their mandibles for food. Here again Nature is their sole guide. Without human or avian suggestion they also learn to drink in the well-known bird fashion; also to bathe, chirp, frolic, and do many other things. Who has ever seen a pet bird in drinking try to lap like a dog, or take in long draughts like a cow or a horse? No; Nature made them birds, and birds they will be. It is noticeable, too, that when birds begin to peck, or bathe, or seek a perch, they do not usually act as if they were deliberately planning to do so, nor as if they were carrying on some process of thought leading to choice, but rather as if they were impelled by Nature to do so. The chirping of birds is mostly, if not wholly, a matter of inheritance. For instance, my little wood thrushes, as soon as they reached a sufficient age, called just like their relatives of the sylvan solitudes; my brown thrashers uttered the labial chirp of the species; my red-winged blackbird exclaimed "Chack! chack!" after the manner of his kind; my bluebirds expressed their feelings in the sad little purr of _Sialia sialis_; my flickers did not borrow the calls of the red-heads, but each clung to its own language; my catbirds mewed like poor pussy in trouble; and so on through the whole list. True, these pets may have heard their parents' calls before they were taken from the nest, but it is not at all likely that they would have remembered them, for at first they only "cheeped" after the manner of most bantlings, and only a good while afterward did they fall to using the adult chirp. Besides, while still in the nest, they must have heard many other bird calls; why did they not acquire them? Heredity has laid a strong hand upon birds, and has drawn sharp dividing lines among the various species. Instinct also plays a large part in moving the bird to sing and to render the peculiar arias of its kind. For instance, a pet wood thrush of mine, secured at an early age and kept far away from all his kith of the wildwood, became a fine musician. And what do you suppose was the tune he executed? It was the sweet, dreamy, somewhat labored song of the wood thrush in his native wilds. He never sang any other tune. I think he sang it better than any wild thrush I have ever heard. It was louder, clearer, more full-toned, but the quality of voice and the technique were precisely the same. Who was his teacher? No one but Nature, heredity, instinct, whatever you choose to call it. There was no wild thrush within a half mile of his cage. [Illustration: Robin]