Nor do these benefits comprise all the claims of birds to the gratitude of man. In tropical America the Agami, _Trophia crepitans_, or Trumpet Bird of Guiana, is domesticated, and so docile in its habits, that it is employed to watch the flocks, which it does with the fidelity and intelligence of a Dog. "The Agami," says M. Monocour, "is not only tamed easily, but becomes attached to its benefactor with all the fondness and fidelity of a Dog. When bred in the house, it loads the master with caresses, and follows all his motions, but is easily offended." It is bold and obstinate, and will attack Cats and Dogs, fighting a tough battle with one of the latter, however considerable his size. In Cayenne the denizens of the poultry-yard are confided to its care; it leads them to their pasture, prevents them from straying to a dangerous distance, and brings them home in the evening, just as a trained shepherd's Dog will do the flocks committed to his care, and it manifests its delight by cries of joy when its master vouchsafes a caress in return for its faithful service. The Kamichi, which belongs, like the Agami, to the same order, possesses similar characteristic intelligence. Like the former, it is sociable and susceptible of education, and becomes a useful auxiliary to the inhabitants of South America. After these brief remarks on the organisation and habits of birds, we proceed to describe the more remarkable species, arranged according to a simple and comprehensive order of classification, placing before the reader the various orders of the class AVES, in the ascending scale which has been adopted in our previous works. AVES--BIRDS. Warm-blooded, vertebrated, biped animals. _Pectoral limbs_, fore-arms or wings organised for flight; feathery _integument_; red blood; _respiration_ and _circulation_ double; _lungs_ fixed and perforated. I. NATATORES, OR PALMIPEDES. Swimming birds, having the toes united by a membrane; legs placed behind the equilibrium; the body covered with a thick coat of down beneath the feathers. They include the following orders and families:-- I. _Brevipennes_, Ostriches, Cassowaries, the Penguins, Auks, Guillemots, and Grebes. II. _Longipennes_, including the Terns, Gulls, Mews, Petrel, and Albatross. III. _Totipalmates_, the Pelicans, Gannets, Cormorants, Frigate Bird, Tropic Bird. IV. _Lamellirostres_, the Ducks, Geese, Swans, Flamingos. II. GRALLATORES. Wading birds, having the legs long and naked from the tibia downwards. I. _Macrodactyli_, Crakes, Coots, Rails, Screamers. II. _Cultrirostres_, Boatbills, Cranes, Herons, Ibis, Storks, Spoonbills. III. _Longirostres_, Avocets, Snipes, Ruffs, Turnstones, Sandpipers, Godwit, Curlews, Gambets. IV. _Pressirostres_, Oyster Catchers, Thicknee Plovers, Lapwings, Bustards, Coursers. III. RASORES.