Iv PALAMEDEIDAE 109 
bill is short and Fowl-lke, with a blunt decurved tip, a covering of 
soft skin, and more or less of a cere; the tibiae are partly naked, 
the entirely reticulated metatarsi moderately long and _ fairly 
stout; the toes are elongated and have strong claws, but only 
rudimentary anterior webs; the wings are ample and somewhat 
rounded, with eleven primaries and about sixteen large second- 
aries; the tail has fourteen broad feathers in Palamedea and 
twelve in Chauna.' Very noticeable are the two sharp spurs on 
the carpal portion of each wing, of which the foremost is the 
biggest ; while in the even distribution of the body-plumage this 
Family recalls the Ratitae and the Spheniscidae. The sexes are 
alike ; the nestlings, where known, are clad in yellowish-brown and 
grey down, the wing-spurs being developed in the earliest stages. 
The following account of the habits of Chawna cristata, the 
Chaja or Chaka, must stand for those of the Family, in default 
of further details concerning the more northern forms. This 
striking species 1s a common resident in the swamps and 
brackish lagoons of Argentina, where the islands of the intricate 
morasses often bold flocks of more than a hundred individuals, 
the separate pairs being said to mate for life. The flight is slow, 
with powerful strokes of the wing, the birds being greatly 
addicted to soaring in spiral circles until they are hardly 
visible, and at times floating lazily upon. the breeze. They 
rise noisily from the ground with laboured action, and are occa- 
sionally seen to perch in trees; but they are by nature waders 
which swim with considerable facility, and, when they do so, 
their bodies shew well above the water, owing no doubt to the 
same pneumaticity which causes a crackling noise to be heard 
when the skin is compressed. The food consists of succulent 
water-plants, seeds, clover, and so forth. The loud cry, uttered 
with the head thrown back when the performer is on the ground, 
may be heard at a distance of two miles, the male giving vent 
to a “cha-ha” and the female replying with a “ cha-ha-li.” 
The regular period for reproduction is the southern spring— 
September and October—but it is a remarkable fact that breed- 
ing takes place also in autumn and even winter; the nest being 
a massive structure of reeds and rushes slightly hollowed above, 
and standing some two feet high with its foundations in water, or, 
1 Gibson, bis, 1880, pp. 165-167 ; Hudson, Argentine Ornithology, ii. 1889, pp. 
119-122. 2 Chauna has a dilatation near the middle of the trachea. 
