Q2 ELEMENTS OF ORNITHOLOGY. 
(Cotinga cerulea) of Cayenne. This last is a type of a group 
of some hundred and ten species to which the Cock-of-the-Rock 
and the Umbrella- and Bell-birds also belong—a group known 
as the Cotingide. 
Yet another exclusively South-American Bird is, as we shall 
hereafter see, of extraordinary interest, owing to its exceptional 
structure, and the divergence of opinion which has existed, and 

The Umbrella-bird (Cephalopterus ornatus). 
exists, as to its true affinities. This is the Hoatzin (Opisthocomus 
cristatus, fig. 97), which inhabits Guiana and the immense Valley 
of the Amazon. When hatched, it has two well-developed 
fingers, each with a claw, and is said to creep about on all fours 
like a Quadruped. 
The curious and rapidly disappearing Huia-bird of New Zea- 
