764 



THE POPULAR SCIENCE MONTHLY. 



The head of the hoactzin is ornamented with a semipendent crest 

 composed of rather long, loose, yellowish feathers, as shown in 

 the figure below. Below, the body is of a dull chestnut, while 

 above it is olive splashed with white. Its large tail is conspicu- 

 ously tipped with yellow, while its wings are short and rounded. 



These birds congregate in loose companies in the undergrowth 

 found upon the banks of streams and sloughs. Here they are 



Fio. 1. The Hoactzin (C. cnstatus). 



easily approached, inasmuch as they are weak fliers and seldom 

 take to wing. They are believed to be polygamous, and it is 

 known that in the manner of their nesting and the appearance of 

 their eggs they strongly remind us of the gallinules and rails. 

 This is a curious circumstance, for it falls into line with another 

 gallinuline character. The claws on the indicial digits of young 

 gallinules are pretty well developed so much so that they can 

 use them to help crawl out of their nests with, by catching on 

 to twigs, and so forth, in their way and neighborhood. These 

 claw joints are even better developed in the hoactzin, where in 

 the young they are more or less functional. Opistlwcomus lives 

 upon fruits, leaves, etc. " Its voice is a harsh, grating hiss, and 

 it makes the noise when alarmed, all the individuals sibilating as 

 they fly heavily away from tree to tree when disturbed by pass- 

 ing canoes" (Bates), In British Guiana it is called the " stink 

 bird," from the disagreeable odor it has, and which, according to 

 Newton, Deville likens to that of a cow house. No fossil forms 

 of opisthocoraine birds are known. 



