SNOW-LIKE MASSES OF COCKATOOS 213 



breed in large numbers on the rocks about Exmouth 

 Gulf, and on some of the islands of Dampier's archipelago, 

 especially those that are surrounded with a fringe of 

 mangroves. Flocks of them may be seen on the north 

 coast which number the birds by tens of thousands ; but 

 they are not so abundant near the colonies, though 1 have 

 seen a large flock hovering over the upper reaches of the 

 Swan. 



A species of gannet {Sula piscatrix) must also be 

 mentioned ; for though I do not know that it is common 

 on the west coast, two were shot by me near Port Grey. 

 They were remarkable for their red legs and feet. 



The cockatoos and parrots are the most characteristic 

 birds of the district. They are most abundant in the 

 interior, especially where the trees form woods and 

 groves. There are at least eight species or varieties of 

 cockatoos in the country between Swan River and Shark 

 Bay. The commonest is the sulphur-crested {Cacatua 

 galeritd), which, in some parts of the country, especially 

 where the rivers are edged with mangrove thickets, may 

 be seen in flocks so great that the trees look as if covered 

 with masses of white wool. If these huge flocks, which 

 on the Gascoyne sometimes number thirty or forty thousand 

 birds, are fired at, the screaming they set up is deafening. 

 There are two varieties of the black cockatoo — Calyptor- 

 hynchus xanthonotus with a yellow-banded tail, and a 

 variety with a red-banded tail, the plumage in both being 

 of a bright sheeny black. These birds are not nearly 

 so abundant as the white kind, and do not go in large 

 flocks. It is rare to see more than twenty or thirty 

 together ; but occasionally they assemble in flocks of a 

 few hundreds, I think for the purpose of migration. 

 Both kinds of these cockatoos, called slender-bills {Lich- 

 metis nasica and L. pertinator)^ are found in the Swan 

 River district in considerable numbers, and are still more 

 abundant in the Champion Bay locality and further 

 north. The beautiful pink C. leadbeateri is occasionally 

 seen in the inland parts of the Swan River district, and 

 has been shot near Perth, while the still handsomer C. 



