The PEACOCK TROGON (_Trogon calurus_) has the central tail-feathers of great length. The feathers of the head, throat, upper breast, and wing-covers are of a bright, metallic green, and gleam with a copper-red and violet lustre; the lower breast, belly, rump, and thighs are purplish red; the inner side of the wings, the quills, and tail are black. The eye is a dull, carmine-red, and the bare patch that surrounds it dark grey; the beak is deep red, tipped and edged with yellow, and the foot brown and yellow. The female resembles her mate, but is somewhat less bright in hue. The length of this bird is fourteen inches and a quarter, and its breadth twenty-two inches and a half. The wing measures seven inches and a quarter, and the tail seven inches; the centre tail-feathers exceed the rest by six inches and a half. Spix first discovered this bird at Rio Negro. THE BEAUTIFUL TROGON. The BEAUTIFUL TROGON (_Calurus Pharomacrus_ or _C. antisianus_)--(See Coloured Plate XXV.)--is recognisable from the Peacock Trogon by a bunch of hair-like feathers on the region of the beak, and by the inferior length of the long feathers on the wing and tail. The coloration of the plumage is almost identical, except that the tail-feathers are quite white underneath, and the beak of a yellowish shade. The body is fourteen inches long; the wing measures seven inches and a half, and the tail six inches and a half. D'Orbigny discovered this bird in Bolivia, where it frequents the vicinity of the rivers. THE QUESAL, OR RESPLENDENT TROGON. The QUESAL, or RESPLENDENT TROGON (_Calurus paradiseus_, or _C. resplendens_), the most magnificent of all these beautiful birds, is adorned with a helmet-like crest, and possesses a most extraordinary development of the feathers on the shoulders, which droop over the wings and tail. The mantle and upper breast are of a brilliant, golden green. The under side is bright carmine-red. The eye is deep nut-brown, the eyelid black, the beak yellow, with a brownish base; the foot brownish yellow. The female has a smaller crest, and the long feathers in her tail scarcely exceed the other tail-feathers in length. In both sexes the head, throat, and upper breast are dark green; the back, shoulders, and upper tail-covers light green; and the lower breast and belly greyish brown. The rump is bright red, the centre tail-feathers are black, those at the exterior white, marked with black. The length of the body is sixteen inches; the wing measures eight inches and one-third, and the tail eight inches and a half. The longest feathers in the male bird's tail exceed the rest by twenty-five inches. [Illustration: QUESALS, OR RESPLENDENT TROGONS (_Calurus paradiseus_, or _C. resplendens_).]