(891) Seicercus xanthoschistus xanthoschistus.
The GREY-HEADED Warbler.
Phyllopneuste xanthoschistos Hodgs., Gray, Cat. B. & M. Nepal and Tibet, p. 151 (1846) (Nepal). Cryptolopha jerdoni. Blanf. & Oates, ii, p. 425.
Vernacular names. Inshushia (Kacha Naga).
Description. Forehead, crown, nape, mantle and back ashy-grey, the centre of the crown paler and the sides very distinctly darker, almost blackish brown; scapulars, rump and upper tail-coverts yellowish olive-green; tail brown edged with green and with the inner webs of the two outer tail-feathers white; a white supercilium from the nostrils to the nape; lores and behind the eye blackish brown; edges of the eyelids, above and below, white; sides of the head and neck grey; below from chin to vent bright yellow.
Colours of soft parts. Iris dark brown; bill above dark horny-brown, below yellow or horny-yellow; legs horny-yellow, yellowish-fleshy or, according to Oates, plumbeous, soles yellow, claws horny-brown.
Measurements. Total length about 100 mm.; wing 45 to 54 mm., generally under 53 mm.; tail 34 to 41 mm.; tarsus about 19 mm.; culmen 9 to 10 mm.
Distribution. Nepal, East to the extreme East of Assam, both North and South of the Brahmaputra and the Chin Hills, where it has been obtained in the higher ranges about Mount Victoria.
Nidification. This pretty little Warbler breeds in the Assam Hills in April, May and June, occasionally having a second brood in July-August. Over most of its range it breeds between 3,500 and 6,000 feet but in the Lakhimpur District it breeds at about 1,000 feet upwards. In this corner of Assam, doubtless due to the nearness of the snowy ranges on either side of the valley, the avifauna at 1,000 feet is much the same as it is elsewhere at 4,000 feet or even higher. The nest is a lovely little ball of vivid green moss, very densely lined with soft vegetable silk or cotton,, the favourite material being the silk from the pods of the cotton-tree. The nest is placed on the ground or low down in among the moss on some boulder or old stump and is very hard to find. I found one beautiful cup-shaped nest fixed in a fork of a fallen branch but this type of nest is quite abnormal. The eggs number four and are pure white, generally fairly glossy, in shape being rather pointed, broad ovals. Fifty eggs average 15.7 X 11.9 mm.: maxima 16.2 X 12.0 and 15.2 x l2.2 mm.; minima 14.1 x 10.5 mm.
The eggs of this species are the most fragile and least glossy of the eggs of this genus.
Habits. The Grey-headed Warbler is confined entirely during Summer to dense forests, either Evergreen or Pine and Fir, but in Winter may be found often in bamboo-jungle and in the secondary growth which grows up in deserted cultivation. It is a lively, cheerful, little bird, catching insects both on the wing and among the branches of trees at all heights from the ground. It has a pretty trilling little song and has a habit of constantly spreading its tail-feathers to show the white of the inner webs. In the breeding-season it accompanies this action with a puffing out of all the body-feathers, drooping and shivering its wings at the same time. It descends to the foot-hills and the adjacent plains in Winter, at which season it is found all over Assam.