The HELMET BIRDS (_Corythaix_). These elegant and brilliantly-coloured
birds are slenderly formed, with rounded wings, of which the fifth quill
is longer than the rest. The tail is of medium size, the beak short and
triangular, furnished with a slight hook at the extremity of the upper
mandible; the nostrils are partially covered by the feathers on the brow,
the plumage is rich; upon the head the feathers are prolonged so as to
form a kind of helmet composed of green feathers. The wings are of an
uniform purplish red, and the eyes surrounded by a bare flesh-coloured
ring. All the various members of this group are remarkably alike, both in
their appearance and mode of life.