CH. Ix YOUTH, MATURITY, AND AGE 287 
a distinct group. All his near kindred have passed 
away, and he stands solitary, a living fossil, the only 
survivor of a number of families that have either 
disappeared, too primitive to hold their own, or have 
advanced to a higher organisation. 
Apparently about as large as a rather under-sized 
Pheasant, the Hoatzin is really considerably smaller ; 
his long tail, his large wings, and his crest suggest a 
larger bulk of body than he really possesses. He and 
his kind are born from eggs that are usually smaller 
than ahen’s, but which vary much in size. His breast- 
bone has a very slight development of keel, and that 
only in its hinder part, and the clavicles, from the 
point where they meet, send back a long bone which 
looks remarkably like a reptilian interclavicle. Among 
the trees and bushes that form a jungle-growth along 
the banks of the Berbice and often overhang its waters, 
Hoatzins are plentiful. When a boat passes they will 
generally remain concealed among the leaves. They 
seldom fly, their large wings having but weak muscles 
to move them. The longest observed flight was no 
longer than forty yards, and that with a considerable 
descent, from a high growth on one bank to a lower one 
on the other. Mere jumps or the very shortest flights 
are more usual when the crack of a gun disturbs them. 
The food consists, as far as is known, entirely of leaves: 
they are crushed in the crop, which is formed of thick 
walls of muscles with outstanding ridges. The nest 
is formed of a few sticks intertwisted. When the 
birds’-nester comes, cutting a way for his boat 
through the bushes, or wading thigh-deep through the 
mud, the old bird makes off upon the wing. The 
