302 THE BIRDS 



build and having strong legs and toes adapted for swimming. They 

 are principally grain feeders, but the young are often supplied 

 with insect food, and herbage of all kinds is frequently devoured. 

 The crop is very large, and in this the food is first macerated, after- 

 wards being ground up in the gizzard with the help of stones and 

 grit swallowed by the birds. Pheasants, partridges, quails, grouse, 

 ptarmigan, turkeys, peafowl, guinea-fowl, the mound-building 

 megapodes, and the crested curassow, are a few members of this 

 group, and amongst the foreign species are many beautiful and 

 remarkable birds of which space forbids description. We must, 

 however, give passing attention to the Hoatzin or Ama, a native 

 of the Amazon Valley, a remarkable bird, included by some 

 naturalists in the Gallinae, and by others placed in a separate 

 order by itself. The sternum is unlike that of any other bird, and 

 the crop is extraordinarily large ; but the chief interest centres in 

 the nestlings, which, when hatched in a rough nest made of sticks, 

 in a bush or tree on the margin of a stream, have well-developed 

 claws on the thumb and index finger of the wings. The little 

 creatures, which are at first naked, almost at once begin to climb 

 about the boughs of the trees, using not only the feet and beak 

 parrot-fashion but the claws of the wings as well, so at this 

 state of their lives they are actually quadrupeds, and approach 

 more nearly the archaeopteryx and the reptilian birds than any 

 other living species. As the young birds develop the wing claws 

 are shed, and the wings assume the ordinary avian form. 



The Psittaci, or Parrots, are a very distinct group of birds, 

 the most notable characteristics being the large hooked bill, which 

 has the upper mandible hinged and overhanging the lower one ; 

 and the formation of the foot, which is termed " zygodactylous " 

 that is to say, the first and fourth toe are permanently turned 

 backwards. The Parrot tribe includes the parrots, cockatoos, 

 macaws, parrakeets, and lories or brush-tongued parrots. In 

 all there are about five hundred species, varying considerably 

 in size, but usually distinguished by their more or less gaudy 

 colouring. The Macaws are, perhaps, the most conspicuous 

 members of the group, their plumage in some cases being absolutely 

 dazzling to the eye ; the Red and Blue Macaw (A fa macce], with 

 its vermilion-red, blue and yellow plumage, and the Blue and 

 Yellow Macaw (A. ararauna), in its feathery garb of bright blue 



