138 TURDIDvE. 



without mud, in the branch of a tree, and lays four eggs, which are 

 described as being pale green marked with purple and brownish 

 red, and measuring about 1 by -72.* 



684. Geocichla sibirica. The Siberian Ground-Thrush. 



Tardus sibiricns, Pall. Reis. Buss. Reich, iii, p. 694 (1776) ; Hume, 



Cat. no. 369 quat. 

 Oreocincla inframarginata, Blyth, J. A. S. B. xxix, p. 106 (1800) ; 



Ball, 8. F. i, p. 70 ; Hume, 8. F. ii, p. 223. 

 Turdulus davisoni, Hume, 8. F. y, pp. 03, 136 (1877). 

 Turdulus sibericus (Pall), Hume # Bar. 8. F. vi, pp. 2-55, 513 ; 



Hume, 8. F. xi, p. 132. 

 Geocichla sibirica (PaU.), Seebohm, Cat. B. M. y, p. 180; Oates, 



B. B. i, p. 4. 



Coloration. Male. The fully adult has the whole plumage slaty 

 black, the margins of the feathers paler ; the outer three pairs of 

 tail-feathers narrowly tipped with white ; a broad white super- 

 cilium to the nape ; the under tail-coverts tipped with white ; 

 axillaries white tipped with dark ashy, and the under wing-coverts 

 ashy tipped white. Males after the second autumn moult are 

 bluish slaty instead of slaty black, but the middle of the abdomen 



* Geocichla avensis. 



Turdus aveusis, Gray, Griffith's ed. Cuvier, vi, p. 530, pi. (1829). 

 Geocichla avensis (Gray), Hume, 8. F. viii, p. 39 ; Seebohm, Cat. B. M. v, 

 p. 167. 



Coloration. Forehead, crown, nape, and hind neck bright chestnut ; upper 

 plumage, wings, and tail dark slaty brown, the lesser and median wing-coverts 

 almost entirely white, and the greater coverts tipped with white ; lores, cheeks, 

 and a portion of the ear-coverts white ; remainder of the head, throat, and 

 upper breast black ; lower breast, abdomen, and sides of the body white spotted 

 with black ; middle of abdomen, vent, and under tail-coverts white ; axillaries 

 white tipped black ; under wing-coverts black tipped white. Wing 4 - 2 ; tail 2 - 5. 

 It is not known how the sexes differ. The above description probably applies 

 to the male only. 



The only record of the occurrence of this species within Indian limits is the 

 statement of Gray that the plate of G. avensis in his work was taken by 

 Mr. Crawfurd from a specimen procured at Ava. Until this habitat is con- 

 firmed, I think it preferable merely to notice this species and thus draw atten- 

 tion to it. This species has never been observed in Burma again since 

 Crawfurd's time. 



I have little doubt that G. avensis is the same bird as G. interpres, Kuhl. 

 The two species are said to differ only in one slight respect. 67. avensis has 

 the greater wing-coverts plain, and 67. interpres has them tipped with white ; 

 but as all we know of the former bird is derived from Gray's figure, too much 

 reliance must not be placed on this character. 



Hume received a specimen of a Thrush from the Malay peninsula (Rumbow) 

 which he identified with 67. avensis. On examining this specimen, which is 

 now in the British Museum, I find that the greater wing-coverts are wanting 

 or in part moulting, and that the new sprouting feathers of this part appear 

 to be tipped with white. The sjiecimen is by no means a good one for the 

 purpose of deciding the question of the identity or difference of the two species, 

 which must for the present remain unsettled. 



