The SECRETARY or CRANE VULTURE (_Gypogeranus serpentarius_), a member of this family, is one of the most extraordinary birds with which we are acquainted, and well deserves a minute description. Its body is slender, its wings long and straight, the first five quills being of equal length, and there are blunt spurs or excrescences on the carpal joint. The tail is of remarkable length, and very abruptly graduated, the two middle feathers, which are slender, extending far beyond the rest. Owing to the very peculiar construction of the feet, naturalists differ as to the classification of this species, and we have therefore assigned it to no particular group. The principal peculiarity of the Crane Vulture's foot is the disproportionate length of the tarsus; the toes are short and the claws of moderate size, blunt, but slightly curved and very strong. The neck is thick, and the head small, broad, and flat at the top; the beak, which is shorter than the head, is thick, powerful, and vaulted, curving abruptly downwards from its base: the hook in which the upper mandible terminates is of moderate size, and very sharply pointed. The cere extends from below the eyes almost to the middle of the beak. The plumage is thick and formed of large feathers, which are prolonged at the back of the head into a crest, composed of six pairs of feathers placed one behind the other, so that they can be either raised and spread, or laid flat one upon another. The cheek-stripes and region of the eyes are bare. In the coloration of the plumage light greyish blue predominates; the top of the head, crest, nape, quills, and tail feathers, with the exception of the two longest, are black, edged with white at their tip; the belly is striped with black and light grey, the legs with grey and light brown; the two centre tail-feathers are greyish blue, tipped with white, and spotted with black towards the extremity; the lower wing-covers are reddish brown. The crest of the female is shorter and her tail longer than that of her mate, her plumage is also lighter; her legs are striped brown and white, and her belly is entirely of the latter hue. The young resemble their mother. The length of the male is from forty-one to forty-three inches; the wing measures twenty-four inches and the tarsus is one foot long. The female is somewhat larger than her mate.