(313) Leioptila gracilis.
THE GREY SIBIA.
Hypsipetes gracilis McClell., P. Z. S., 1839, p. 159 (Assam). Lioptila gracilis. Blanf. & Oates, i, p. 197.
Vernacular names. None recorded.
Description. Forehead, crown and lores black, paling on the nape and ear-coverts and blending with the rich slaty-brown of the hind neck, back and scapulars; rump and upper "tail-coverts ashy-grey ; lesser, median and primary coverts, and outer feathers of the greater coverts black; remaining greater coverts and innermost secondaries bluish-ashy, edged with black, and the basal portions more or less white; quills black, the earlier primaries edged with hoary-grey on the outer webs; central tail-feathers bluish-grey with subterminal black bands, the black bands and grey tips increasing in extent until the outermost feathers are entirely black with grey tips; chin, throat and cheeks white, becoming fulvous on the breast and abdomen, the sides of which are washed with lilac; vent and under tail-coverts buff.
Colours of soft parts. Iris red to bright crimson, reddish-brown in young birds; bill black; legs and feet brown to brownish-black, the feet and claws darker still.
Measurements. Total length about 235 to 245 mm.; wing 92 to 97 mm.; tail about 130 to 140 mm.; tarsus about 30 mm.; culmen about 20 mm.
Distribution. Hills South of the Brahmaputra, Manipur and Chin Hills.
Nidification. This bird breeds freely in the Khasia Hills, where it is common between 4,000 and 6,000 feet. In the early sixties Godwin-Austen took its nest in the Umiam Valley and the next nest was taken by myself in 1905 in the same spot; since then many nests have been taken, all in pine-trees and all built in the thick tufts at the ends of branches. They are made of green moss and lined with roots and are rather massive and well-built cups. The eggs are generally two only in number, sometimes three and very rarely four. In appearance they are very like weakly coloured Blackbirds' eggs, pale greyish or greenish blue, lightly freckled and blotched all over with pale reddish; a few eggs approach the Actinodura type of egg with bolder markings and spots. Sixty eggs average 23.9 x 17.7 mm. The breeding season lasts from the middle of May to July and the birds may be found during these months anywhere between 4,000 feet and the highest peaks.
Habits. The Grey Sibia is essentially a bird of pine-forests, outside of which it is but rarely met with except in the cold weather months, when it wanders down to about 3,000 feet in any kind of tree-forest. It flies fairly well, haunting the tops of the pines in small flocks or pairs, working the branches for insects as assiduously as other species of this family. Its call is a fine, clear treble note but if. has many others of a conversational character though it is not a noisy bird.