356 ox BIRDS FEOXI JfORTH AXD WORTH-WEST AUSTRALIA. [May 3, 



In addition to these, tbree specimens (two females and one male) 

 were collected by Dr. Dahl in 1894-95 in three different parts of 

 Arnhem Land (S. Alligator River, Mt. Showbridge, and Howard 

 Creek). 



There is no observable difference between the specimens from 

 Queensland and N. Australia as regards size, colouring, length 

 of the crest, length of the wings, tail, &c., the bill alone being 

 considerably larger in all three specimens from N. Australia than 

 that of those from Queensland, as will be seen from the sub- 

 joined measurements : — 



Specimens from Queensland. 



Female .... Culmen 45 millim. ; genys 30 millim. 

 Male „ 46 „ „ 32 „ 



5) ?1 ^-*- 99 99 -'^ 99 



Specimens from N. Australia. 



Male Culmen 55 millim. ; genys 37 millim. 



Female .... „ 55 „ „ 35 „ 



,, .... ,, 56 ,, „ ob ,, 



As regards the present specimen of C. slellaius, the difference 

 in the size of body between it and the larger species is striking. 

 On the other hand, the difference in the size of the bill is com- 

 paratively less when compared with the specimens from Queensland. 



On account of insufficient materials, it is impossible to determine 

 whether the unspotted body in the present female is an invariable 

 and specific characteristic by which this species can be separated 

 from the larger species (in which the females are known to be 

 always spotted). 



Hab. Dr. Dahl did not meet with 0. stdlatus in separate flocks, 

 but only in the company of the larger species. 



The preserved specimen was shot amongst C. macrorht/nchits, 

 which appears everywhere throughout Arnhem Land, where it was, 

 as a rule, seen in flocks of about six individuals. Likewise in the 

 neighbourhood of Roebuck Bay (further to the southward) these 

 large black Cockatoos were numerous, and assembled in great flocks, 

 especially during the dry season, at those spots where water was 

 to be found. Many were shot as food for the expedition. 



Amongst these flocks of 0. macrorhynchus there were occasionally 

 seen individuals which appeared to be smaller than the others, and 

 which might be assumed to have been O. stellatus. 



5. PSEPHOTUS DISSIMILIS, sp. nOV. 



Four specimens (one male, three females), from Mary River, 

 Arnhem Land, May 1895. 



The male and one female are fully grown, with rather worn 

 plumage ; two other females are younger, freshly moulted. 



Nearest to P. chrysopteryyius Gould, 1857, but lacks the yellow 

 band across the forehead ; the crown is chestnut, the lower parts 



