(587) Geocichla citrina citrina.
The Orange-headed Ground-Thrush.
Turdus citrinus Lath., Ind. Orn., i, p. 350 (1790) (Cachar). Geocichla citrina. Blanf. & Oates, ii, p. 140.
Vernacular names. Daokat-gajauiaba (Cachari).
Description.— Adult male. Whole head and lower parts to vent orange-chestnut, darkest on the head and paler below, the centre of the abdomen sometimes almost albescent; upper plumage and wing-coverts dark bluish grey, each feather edged paler, a conspicuous wing-spot of white formed by the broad white tips of the median wing-coverts : primaries and outer secondaries blackish brown, edged externally with pale blue-grey; tail dark brown, faintly cross-rayed and with the central feathers tinged with blue-grey; vent and under tail-coverts white.
Colours of soft parts. Iris hazel to deep brown; bill dark horny brown; legs and feet creamy yellow to fleshy pink.
Measurements. Total length about 225 mm.; wing 103 (one) and 109 to llM mm.; tail 67 to 69 mm.; tarsus about 33 mm.; culmen about 19 to 20 mm.
Female. Like the male but with the upper plumage (wings and tail) olive-brown instead of blue-grey, the feathers faintly edged with olive-yellow.
Colours of soft parts as in the male. Measurements. Wing 100 to 106 mm.
Nestling. Above dark brown, the feathers with pale central striae, the head and mantle orange-brown with darker edges and pale centres, the lower plumage dull pale orange-white heavily barred with black. Young males acquire the blue upper plumage direct from the nestling plumage and have no intermediate plumage like that of the female. The median wing-coverts are tipped with buff instead of white. It is interesting to note that young birds show signs of the two black cheek-bars so conspicuous in adult G. c. cyanotis.
Distribution. The Himalayas from Murree, Simla, and Garhwal to Assam, very rare in the West, and getting more and more common to the East, almost the whole of Burma to the extreme South of Tenasserim, East to the Shan States, Siam, Langbian Beak in Annam (Robinson & Kloss) and Yunnan. In India in winter it moves to the foot-hills of the Himalayas and adjacent plains, and individuals often wander far afield. Thus in the Museum there are typical specimens from Mirzapur, Baipur, Madras and one from Ceylon and three others from this island are in the Colombo Museum. Recently Robinson and Kloss have also recorded it from Sumatra. In Bengal they are not very rare in December and January and they come well into the Behar Plains. Birds from Szechuan are nearer to G. c. aurimaculata from Hainan, but much bigger with wings measuring 108 to 113 mm.
Nidification The Orange-headed Ground-Thrush breeds throughout its range between 1,000 or 2,000 and 5,000 feet, occasionally a little higher than this. It lays principally in May and June but frequently also in July, whilst I found fresh eggs as late as the end of August. The nest varies considerably. It is cup-shaped and rather shallow, the materials consisting of line twigs, grass, dead leaves, scraps of bracken and invariably a considerable amount of green moss outside and a lining of line roots and fern rachides. Sometimes it is neat and compact and sometimes very loosely put together and untidy. It is placed in high bushes or small trees at any height from the ground between and 15 feet. The eggs number three or four, rarely the. In colour they vary from pale green-blue, pinkish stone, or cream, whilst the markings vary from freckles of reddish blown profusely distributed all over the egg as in a Blackbird's to quite bold blotches and spots of rich reddish purple with the pale ground showing up well between them. They are in fact like many other Indian Thrushes' eggs such as Tardus dissimilis but differ from all these in their glossy surface and hard, close texture. One hundred eggs average 25.6 x 19.3 mm.: maxima 27.7 x 20.0 and 25.5 x 21.3 mm.; minima 21.0 x 18.5 and 27.8 X 17.1 mm.
Habits. This Ground-Thrush is essentially a bird of deep forest, though it is sometimes found in the thin cover on recently deserted patches of cultivation or in bamboo-jungle. It prefers deep, shady forests of evergreen character with an undergrowth of bushes, ferns and luxuriant wet green growths, where it potters about, on the ground in its search for berries and insects. The crevices between the moss-covered boulders it hunts for beetles and spiders, and the fallen leaves and rubbish it turns over and over for the same purpose. It has a few sweet notes in the breeding-heason, hardly rising to a song and it has also some quite harsh notes as well. It is a tropical Thrush and is only found in hot forests from 6,000 feet almost to the foot-hills in Summer and well into the adjacent Plains in Winter. At the same time it is not migratory in the true sense of the word, though individuals may wander very far from their usual haunts.