AVES. 
167 
speckled with ash-colour and white ; beneath, the feathers are 
tinged with light ferruginous; tail cream white, barred with 
black and cinereous; bill black ; irides orange-yellow; legs and 
toes covered with a buff-coloured down ; claws dusky. Thir¬ 
teen inches long. Inhabits Europe and America. 
ORDER II—OMNIVOROUS BIRDS. 
Beak robust, medium-sized, and sharp on the edges; upper 
mandible more or less convex, and notched at the point; feet 
with four toes, three before and one behind; wings of medium 
length; quill feathers terminating in a point. 
Genus 1. — OPISTHOCOMU S.—Illiger. 
Generic Character. —Bill short, thick, convex, bent down, 
wards at point; base dilated laterally; under mandible strong; 
angular at its termination; nostrils near the middle of the bill, 
covered by a membrane ; legs strong; tarsus, shorter than the 
middle toe; toes edged by a rudimentary membrane; first quill 
short, the next four graduated, and the sixth longest. 
Opisthocomus cristatus. —The PIoatzin. 
Plate LI. fig. 7. 
White above and black beneath ; head with a long somewhat 
pendulous crest; a naked rufous space round the eyes; wings 
with two paler bands; tail wedge-shaped; with a fillet of yel¬ 
low. Twenty-two inches long. Inhabits Guiana. 
Genus 2. —BUCEROS.— Linnaeus. 
Generic Character. —Bill large, long, convex; curved from 
the base; edges serrated, with a large horny protuberance near 
the base of the upper mandible rising into a crest; nostrils be- 
