100 



PARROTS. 



The cockatoos are readily 

 distinguished by the presence of 

 a crest of feathers on the head, 

 which is wanting in all the mem- 

 bers of the next family, with 

 the exception of the peculiar 

 horned and Uvsean parraquets 

 (Nymphicns), respectively from 

 New Caledonia and the island 

 of Uvsea in the Loyalty Group, 

 An absolutely distinctive feature 

 between the two families is, how- 

 ever, to be found in the skull. 

 Thus in all the cockatoos the 

 socket of the eye is surrounded 

 by a complete ring of bone, from 

 the lower border of which is 

 given off a process extending 

 backwards to the hinder part of 

 the skull; whereas in the true 

 parrots (Psittacidce) this ring is 

 generally incomplete, while in 

 such instances as it is entire, it 

 lacks the posterior bony process. 

 As minor characters, it may be 

 mentioned that the nostrils open 

 in a cere which is not much 

 swollen, and is generally naked, 

 although occasionally feathered. The bill is of great depth, and usually very 

 short, the upper mandible being generally much compressed, with its hook at right 

 angles to the axis of the base. In all cases the metatarsus is extremely short. 



The cockatoos are characteristic of the whole Australasian region, ranging 

 as far west as the islands of Celebes and Lombok, and also represented in 

 the Philippines; eastwards, however, their range is limited by the Solomon 

 Islands, and they are consequently unknown in New Zealand. With the exception 

 of the aberrant cockatiel (Callopsittacus) of Australia, which constitutes a separate 

 subfamily, the whole of the members of the family are characterised by their 

 short and broad tails. Their coloration differs markedly from that of the other 

 groups of the order. In the majority of the species white is the predominant 

 colour, but this may be more or less tinged with red or yellow, more especially 

 in the crest and on the under surface of the tail. In the rose-breasted cockatoo 

 the whole breast is, however, red, while the upper surface of the body, together 

 with the wings and tail, are various shades of grey, while the ganga is all grey 

 with the exception of the red head. In other species the prevalent tint is black 

 or dark blackish brown. All lack the green, so characteristic of the parrots in 

 general, although a tinge of this colour exists on the wings of the ganga. 



COCKATOOS. 



