HIEFiACU'EA. 279 



procured in the same locality is an adult leniale slightly richer rufous on the upper parts. 

 These birds from King George's Sound, Western Australia, and from Yandembah Station, New 

 South Wales, I look upon as tlie true Hicracidca hcvi^nra of Vigors and Horsfield. Of intermediate 

 forms there are two adult males, one obtained at Fairfield, eighteen miles south of Sydney, and 

 another procured by Mr. W. \\'. Thorpe at Randwick, a suburb of the metropolis. A more 

 rufous form on the upper parts, but witii the under surface like //. iiruiitalis, is a male procured by 

 the late Mr. K. Broadbcnt, near Launceston, Tasmania. Of course it does not follow that finding 

 rufous and brown birtls in company signify they are one and the same species, for how frequently 

 are lilaiius axillavis and /■, . scn'p/iis found together, but one cannot get away from the fact that 

 intermediate forms occur, and they are certainly not the immature or young stage of llicrandca 

 oricutalis. We have in the Australian Museum Collection specimens of the latter, from the 

 nestling to the adult, but not the young stage of H. hcrigoi-n. I, therefore, intend at present 

 to keep the two separate, although I may not be correct in doing so. Look at the difference 

 between a light and dark specimen of Ninniiis morphnoidcs; on the other hand I have never 

 seen a typical tlici'ihulai ln-ngoi'ii, that is sandy-brown above and almost pure white below, that 

 was obtained in Tasmania. 



.\s the type of llicraiidia liii'igoi'it was obtained by Caley in New South Wales, I have 

 taken the foregoing descriptions from specimens obtained in that State, lixamples, however, 

 from King George's Sound, Western Australia, have the thighs a decided rufous, and are of a 

 darker rufous on the upper parts, and also smaller. Wing of adult male ii inches; of adult 

 female 12-7 mches. 



There is nothing to distinguish between the two forms in habits, food and nidification, when 

 they construct a nest_at all, for more frequently they reline with a few green leaves the deserted 

 tenement of another species, often that of a bird of prey, and also the disused nests of the Crow 

 (Coitus coi'oiioidfs ) and the Raven ( Coroue austvalis). \s the two forms are often found together, 

 and are widely distribiUed over Australia, it is impossible to tell to which eggs belong unless 

 one carefully notes the parents, or shoots them at the nest. The late Mr. K. ?I. Bennett, a 

 keen observer, and a lield naturalist of long and varied experience, recognised two species of 

 Hufacidca, and as he procured the birds when taking the eggs of //. hii'lgoi'ii, I have described 

 only the specimens taken by him. 



Dr. W. Macgillivray writes me as follows from Broken Hill, m South-western New South 

 Wales: — "The lighter Brown Hawk (Himuidca bti-igoi-n) appears to shade into the other species, 

 /f. uricntalis. Several nests have been found, but are indistinguishable from those of the common 

 bird. It occurs, I should think, in about the proportion of one to two hundred of the other, and 

 its habits and general economy are the same." 



Dr. .\. M. Morgan, who accompanied Dr. A. Chenery during a trip made from Port Augusta 

 to the Gawler Ranges, South .-\ustralia, in August, 1900, writes :—" Both the light and dark 

 forms of Brown Hawk were very plentiful, and often seen in company. Several nests were seen 

 in course of construction, but none with eggs. On the 9th August a Dingo was disturbed while 

 feeding upon one of tliese birds. .\s the carcass was iiuite fresh, and in the middle of an 

 uninhabited salt-bush plain, the bird had probably been caught by the dog." 



Probably referrable to this form are the following notes of ?\lr. Chas. G. Gibson, late 

 Assistant Government Geologist of Western Australia: — ".At Lawler's, in the East Murchison 

 District, Western Australia, I took a nest of the Brown Hawk, with three fresh eggs, on the 

 19th September, 1906, and on the i6th October following found a nest at Darlot with three eggs 

 just upon the point of hatching. The latter nest consisted of a few green leaves placed on the 

 debris in a basin-shaped depression measuring eighteen inches in diameter by nine inches in 

 depth, in the top of a trunk of a broken hollow White Gum, and surrounded with a thick bunch 



