(858) Phylloscopus griseolus.
The Olivaceous Tree- Warbler.
Phylloscopus griseolus Blyth, J. A. S. B., xvi, p. 443 (1847) (Calcutta) Phylloscopus indicus. Blanf. & Oates, i, p. 404.
Vernacular names. None recorded.
Description. Upper plumage earthy-brown, sometimes faintly tinged with olive on the rump; wing-feathers dark brown edged paler; rectrices brown, edged paler, and the outermost pair, or two pairs, narrowly tipped with white; supercilium from nostrils to nape yellow, huffish posteriorly; lores and line through the eye brown ; sides of head mixed brown and buff; lower plumage buffy-yellow, dusky on the breast and flanks and often pure yellow on the centre of the abdomen; axillaries and under wing-coverts brown.
Colours of soft parts. Iris dark brown; bill blackish above, pale yellowish or greenish horny below; legs and feet greenish yellow.
Measurements. Total length about 130 to 140 mm.; wing 58 to 66 mm.; tail 47 to 50 mm.; tarsus about 23 mm.; culmen 10 to 11 mm.
Distribution. Afghanistan, Baluchistan, Turkestan, Bochara to Altai, Kashmir and Tibet. In Winter South to the Punjab (rare), Central India, Behar, Bengal, Assam and N.W. Burma.
Nidification. Nests, eggs and young were found by Mr. H. Whistler during June and July at and about Lahul and Spiti between 11,500 and 13,500 feet. The nests he describes as roughly made globes about the size of a cocoanut, composed of grass, strips of bark, etc., densely lined with feathers and placed quite low down in a Juniper bush, Gooseberry-bush or dwarf Willow. A distinctive feature of the nest seems to be the large entrance-hole, placed near the top rather than at the side of the nest. The eggs number four and are white spotted with dull red, mostly in a broad zone at the larger end. Mr. Whistler's series varied from 17.0x12.0 to 17.5 x 13.0 mm. Whitehead found them breeding freely on the Safed Koh Range and in the Kurram Valley between 10,000 and 12,000 feet, and Col. H. Delme-Ratcliffe obtained them in July, evidently breeding, in Baluchistan at. Ziarat at about 8,000 feet.
Habits. Although it has not been often recorded thence, this Warbler is doubtless a common Winter visitor to the Punjab and North-West Province, as well as to the whole of Northern India as far East as Dibrugarh in Assam, where Dr. H.N. Coltart. and I found it very numerous in January and December. It prefers big-tree cover in this season, though it may sometimes be been scrambling about in bushes or even feeding on the ground itself. It has a habit, not shared to the same extent by any other Willow-Warbler, of running about the trunks and larger horizontal branches of big trees just like a Tree-Creeper.