CURASSOWS AND GUANS. 443 
the greater part of the plumage black in both sexes. In two species the under- 
parts and under tail-coverts are chestnut, the first having the tail-feathers tipped 
with white and the second with chestnut, while in the third all these parts are 
white. All three may be distinguished from the curassows by their elevated and 
vaulted upper mandible and the want of curling of the crest-feathers. 
The last genus contains only the curious pauxi curassow 
(Pauxis pauaxi) of the north-western parts of South America, 
remarkable for the large, fig-shaped blue casque on the forehead. The male has 
the entire plumage black, except the under- parts, under tail-coverts, and the 
tips of the tail-feathers, which are white; in the female the back, wings, and breast 
being chestnut, paler on the flanks, and barred and mottled with black. 
To the second group, with the width of the bill at the base 
greater than the height, belongs the rare Derbian guan (Oreophasis 
derbianus), from the wooded 
slopes of the Volean de Fuego 
in Guatemala. The characteristic 
features of this bird are the 
elevated, straight, deep scarlet 
horn on the top of the head 
between the eyes, and the densely 
feathered base of the upper 
mandible. In both sexes the 
Pauxi Curassow. 
Derbian Guan, 
general colour of the head and 
upper-parts is black glossed with 
dark green, the base of the throat 
being almost naked, the front of 
the neck and breast white shad- 
ing into buff on the sides, with 
dark shaft-stripes to the feathers, 
and the remainder of the under- 
parts brownish black, while there is a wide white band across the middle of the tail. 
A more numerous group is that of the guans (Penelope), in- 
cluding fifteen species from Central and South America. In all these 
the chin and throat are generally naked, with a wattle, and there is a large naked 
space surrounding the eye. An allied form (Penelopina nigra), with the plumage 
of the sexes different, occurs in the highlands of Guatemala, the male being entirely 
black, glossed with green, and the female rufous above barred with black, and 
beneath sandy mottled with dark brown. The habits of all these birds appear to 
be very similar; during the breeding-season they are only found in pairs, while at 
other times they congregate in large flocks, always frequenting the forest, and 
passing the greater part of their time in the largest trees, when not engaged in 
searching for fallen fruits and insects. In the next genus (Ortalis), including 
seventeen Central and South American forms, the throat is naked as in the two 
last, but there is a thin band of stiff-shafted feathers down the middle. The only 
member of the family which enters North America is the chachalaca (0. vetula), 
which has a wide range, extending from Southern Texas through Eastern Mexico 



DERBIAN GUAN. 
Guans. 
