WHISTLING EAGLE. 
Halinertus sphenurus Heine and Reichenow, Nomencl. Mus. Heine, p. 267, 1890. 
Haliastur sphenurus territori Mathews, Austral Av. Rec., Vol. I., p. 88, 1912 : Mary 
River, Northern Territory. 
Ictiniastur sphenurus Mathews, ante, p. 146. 
Distribution. Australia (not Tasmania). Extra-limital. 
Adult male. Upper-parts pale brown with pale spear-head markings on the upper wing- 
coverts, mantle and back; the scapulars pale rufous towards the base mottled 
with brown ; bastard-wing, primaiy-coverts and quills black, the iimer webs of 
the latter rufous mottled with brown, the innermost secondaries brown at the 
tips and rufous towards the base; the second, third, fourth and fifth primaries 
incised on the outer webs and first to the fifth on the inner webs ; tail-feathers 
dark grey tinged and mottled with rufous towards the base ; crown of head and 
hind-neck brown lined with buffy-white, becoming ochreous-buff on the sides of the 
face and throat ; the feathers on the fore-neck and breast lanceolate in form, 
creamy-white fringed with brown on the apical portion; abdomen, thighs, and 
under tail-coverts similar in colour but the feathers are normal in shape like the 
axillaries and under wing-coverts. Bill brown ; eyes black ; feet cream. Total 
length 600 mm. ; culmen 28, wing 409, tail 250, tarsus 58. Figured. Collected 
at Ning-bing, 50 miles N.E. of Wyndham, North-west Australia, on the 30th 
of May, 1911. 
Adult female. Similar to the adult male but larger. Wing 427 mm., culmen 29. Collected 
at Napier Broome Bay, North-west Australia, on the 30th of July, 1910. 
Nestling. Covered with buff-coloured down, darker on the head and rump. 
An example five weeks old is covered with white down, with brown feathers showing 
through, with wide buff-coloured centres ; the wing-feathers darker with buff tips. 
Immature. Has the head lighter than in the adult, the feathers of the mantle, neck and 
under-surface buff with darker edges ; upper-surface dark brown, each feather with 
a buff pear-shaped tip ; tail as in the adult ; primaries and secondaries black with 
buff tips. 
As the bird grows older it gets lighter, the markings on the upper-surface become 
smaller and are almost white. 
N est. Composed of sticks and lined with leaves. Outside measurements : 26 to 30 inches 
Avide, 12 deep ; inside, 6 iuches wide by 3 deep. 
Eggs. Clutch two. Bluish-white. The markings are most varied, from sparsely spotted 
with lavender to large blotches of reddish-brown. Axis 52-55 mm. Diameter 
42-44. (April to July, Alexandria.) 
Breeding-season. Practically all through the year. \ 
This common bird was not discriminated by the early travellers, but in 
the Gen. Synops., Suppl. II., p. 18, 1801, Latham described a bird under 
the title “ Cinereous E(agle) ” thus : 
“ This is of a large size ; the bill is large and black : legs the same ; 
the general colour of the plumage deep brown, but the under-parts are 
much paler, and the wings much darker than the rest ; the rump and 
tail are very pale ash-colour, nearly white. 
“ This inhabits New Holland, and from its make and shape seems 
nearly allied to the Cinereous Eagle'"' 
VOL. V. 
161 
