The nestling resembles the adult female, but has the margins of the feathers more extended, causing a squamated appearance. The young male assumes the chestnut of the adult very rapidly and acquires the greater part of it before the autumn moult.
The females and young of this and the next species cannot be discriminated with certainty ; but the females of P. solitaria are generally suffused with rufous on the under wing- and tail-coverts.
Length about 9*5 ; tail 3*4 ; wing 4-9 ; tarsus 1*2 ; bill from gape 1-2.
Birds of this species in typical plumage are only found in Japan and the islands of the China seas. Further west the males always exhibit some admixture of blue with the chestnut of the lower parts. The only bird killed within Indian limits that I have been able to examine at all approaching a typical Japan bird is from the Andainans. On examining all the available specimens of Blue Rock-Thrushes killed in the Indian Empire, I find that out of 102 birds from the west of the longitude of Calcutta only 8 exhibit a trace of red ; of 30 specimens from Assam down to Rangoon, only 7, and out of 72 Tenasserim birds only 27 show any red. This red is generally present on the under tail-coverts, and only in a few-cases extends to the abdomen in varying quantities. The cause of this variation is unknown, but may be attributed either to climatic causes or to the interbreeding of P. cyanus with P. solitaria.
Distribution. Birds exhibiting red in the lower plumage are found in Nepal, Sikhim, Dacca, Cachar, the whole of Burma and the Andamans. This species visits the Empire in the winter only, and at this season is found also in Southern China, extending down to the Malayan islands. It breeds in Japan and Northern China.
693. Petrophila cyanus. The Western Blue Itock-Tlimsli.
Turdus cyanus, Linn. Syst. Nat. i, p. 296 (1766). Petrocincla pandoo, Sykes, P. Z. S. 1832, p. 87 ; Horsf. $ M. Cat. i, p. 186. Petrocincla cyaneus (Linn.), Blyth, Cat. p. 164. Petrocincla affinis, Blyth, J. A. 8. B. xii, p. 177* (1843) ; id. Cat. p. 164 ; Horsf. $ M. Cat. i, p. 187. Petrocossyphus cyaneus (Linn.}, Jerd. B. I. i, p. 511 ; Hume fy Henders. Lah. to Yark. p. 190. Cyanocincla cyanus (Linn.), Hume, N. 8f E. p. 226 ; Hume fy Dav. S. F. vi, p. 247 ; Hutne, Cat. no. 351. Mouticola cyanus (Linn.), Anders. Yunnan Exped., Aves, p. 611 ; Legc/e, Birds Ceyl p. 460 ; Seebohm, Cat. B. M. v, p. 316 ; Gates. B. B. i, p. 11 ; Barnes, Birds Bom. p. 169. Petrophila cyana (Linn.}, Gates in Hume's N. fy E. 2nd ed. ii, p. 105.
The Blue Rock- Thrush, Jerd. ; Shama, Hind, in the South ; Pandu, Mahr. ; Poda kachi pitta, Tel. ; Ninyri-pho, Lepch.
Coloration. Male. After the autumn inoult the whole plumage is bright blue, most of the feathers with white fringes and sub-terminal dark bars ; a supercilium, the cheeks, throat, and ear-coverts brighter than the other parts ; lores blackish ; wings and
