Probably the perch-songster among our ordinary birds that is most regularly seized with the fit of ecstasy that results in this lyric burst in the air, as I described in my first book, "Wake Robin," over thirty years ago, is the oven-bird, or wood-accentor--the golden-crowned thrush of the old ornithologists. Every loiterer about the woods knows this pretty, speckled-breasted, olive-backed little bird, which walks along over the dry leaves a few yards from him, moving its head as it walks, like a miniature domestic fowl. Most birds are very stiff-necked, like the robin, and as they run or hop upon the ground, carry the head as if it were riveted to the body. Not so the oven-bird, or the other birds that walk, as the cow-bunting, or the quail, or the crow. They move the head forward with the movement of the feet. The sharp, reiterated, almost screeching song of the oven-bird, as it perches on a limb a few feet from the ground, like the words, "preacher, preacher, preacher," or "teacher, teacher, teacher," uttered louder and louder, and repeated six or seven times, is also familiar to most ears; but its wild, ringing, rapturous burst of song in the air high above the tree-tops is not so well known. From a very prosy, tiresome, unmelodious singer, it is suddenly transformed for a brief moment into a lyric poet of great power. It is a great surprise. The bird undergoes a complete transformation. Ordinarily it is a very quiet, demure sort of bird. It walks about over the leaves, moving its head like a little hen; then perches on a limb a few feet from the ground and sends forth its shrill, rather prosy, unmusical chant. Surely it is an ordinary, common-place bird. But wait till the inspiration of its flight-song is upon it. What a change! Up it goes through the branches of the trees, leaping from limb to limb, faster and faster, till it shoots from the tree-tops fifty or more feet into the air above them, and bursts into an ecstasy of song, rapid, ringing, lyrical; no more like its habitual performance than a match is like a rocket; brief but thrilling; emphatic but musical. Having reached its climax of flight and song, the bird closes its wings and drops nearly perpendicularly downward like the skylark. If its song were more prolonged, it would rival the song of that famous bird. The bird does this many times a day during early June, but oftenest at twilight. The song in quality and general cast is like that of its congener, the water-accentor, which, however, I believe is never delivered on the wing. From its habit of singing at twilight, and from the swift, darting motions of the bird, I am inclined to think that in it we have solved the mystery of Thoreau's "night-warbler," that puzzled and eluded him for years. Emerson told him he must beware of finding and booking it, lest life should have nothing more to show him. The older ornithologists must have heard this song many times, but they never seem to have suspected the identity of the singer.