(451) Certhia discolor discolor.
THE SIKKIM TREE-CHEEPER.
Certhia discolor Blyth, J, A. S. B.? xiv, p. 580 (1845) (Darjeeling) ; Blanf. & Oates, i, p. 331.
Vernacular names. Saddyer-pho (Lepcha).
Description. Upper plumage dark brown, streaked with fulvous ; rump and upper tail-coverts bright ferruginous; tail bright reddish-brown with red shafts and obsoletely cross-rayed; wings dark brown with the usual fulvous, black-edged band across all but the first four primaries ; most of the quills tipped with white and the later ones with a fulvous streak near the end of the outer web; lower plumage earthy-brown, paler and fulvescent on the posterior flanks and abdomen; under tail-coverts ferruginous; a cheek-stripe rufous or fulvous-rufous; under wing-coverts and axillaries white.
Colours of soft parts. Iris dark brown to red-brown; bill above dark horny-brown, almost black on culmen, below pale horny; legs and feet pale fleshy-brown or pale brown.
Measurements. Wing 67 to 71 mm.; tail 75 to 77 mm.; tarsus about 18 mm.; culmen 13 to 15 mm.
Distribution. The Himalayas from Nepal to E. Assam, both North and South of the Brahmaputra.
Nidification. The only nests and eggs of this bird recorded appear to be those taken by myself in North Cachar and the Khasia Hills. In these hills I found the bird very rare and breeding only in the stunted oak forest in the former district and in pine-woods in the latter. In neither case did they breed below 5,000 feet. The nests are the usual pads of moss inside a broken piece of bark but in the few I saw all had fairly thick linings of fur either of the Bamboo-rat or of a shrew. They were placed between 12 and 30 feet from the ground and they contained from 3 to 5 eggs. These are typical Tree-Creepers' eggs and some are not separable from brightly coloured pink eggs of himalayana and familiaris but as a whole they are much redder eggs, the spots being almost a pure red or pinky-red. Twenty-four eggs average 16.3x 12.5 mm., and the extremes are 17.5x 12.9 and 17.4x 13.0 mm. and 15.2 x 12.3 and 15.4x ll.0mm. The birds are early breeders, commencing in early April and continuing until the second week in May.
Habits, The Sikkim Tree-Creeper is found north of the Brahmaputra between 6,000 and 10,000 feet but on the south of that river between 5,000 and 8,000 feet or a little higher than this is the Naga Hills. In its habits generally it is like all other Tree-Creepers but it seems to keep much to the interior of forests whether of pine or other trees and it is a very shy, quiet little bird, resenting observation more than most of the other members of the genus.