Of Cuckoos the British Naturalist knows of three species; the Great Spotted Cuckoo, inhabiting chiefly the northern and western coasts of Africa, and only now and then paying a short visit to these northern climes; the Yellow-billed, or American Cuckoo, or Cowcow, as some call it, which is a more frequent, although still a rare visitant, and the Common Grey species, termed _Cuculus canorus_, that is, the Musical Cuckoo, with whose curious cry--_cuck-oooo_, most of our readers must be familiar. It may not be generally thought that there is much music in this _monotonous_, that is, single-toned call, but we are assured by a competent authority, that this is the only feathered performer who sings in strict accordance with musical numbers, its notes being the fifth and third of the diatonic scale. But be that as it may, the cry of the Cuckoo is extremely pleasant to most ears, when first heard, soon after the bird arrives in this country, which is sometimes about the middle of April, "in April, come he will," says the old proverb; we know that the fresh floral season of sunshine and country delights, has fairly set in, and all through the summer, to the time of his departure, in August or September, we love to listen to the far-away, dreamy kind of call, for it seems like an invitation to 'follow, follow,' some invisible leader, through greenwoods and flowery dingles, and into scenes of quietude and peace; then, too, there is a kind of mystery about it which excites the curiosity, for who ever sees the utterer of these dreamy sounds. We are inclined to say with Wordsworth,-- "Oh, Cuckoo, shall I call thee bird, Or but a wandering voice." And indeed the Cuckoo is a flying and feathered marvel altogether; we should fill this book were we to repeat all the strange tales that have been told about it, and by grave authorities too, from Aristotle of ancient Greece, to Dr. Jenner, and the rest of modern England. Amid all the disputations that have arisen upon the points of this bird's natural history, we can only clearly gather that it is a summer migrant, coming and going at the times just mentioned; that while with us it is to be found in all wooded and sheltered parts of the island, frequenting most parks and pasture-grounds, groves and thickets, it is more likely to be seen at early morning and evening, than during the broad daylight, and its cry has been heard at all hours of the night, proving it to be somewhat nocturnal in its habits,--_nox_, you know is the Latin for night, and from thence comes this word.