White-breasted Dippers. 385 



two forms of Dipper. Oue of them is C. leucogaster, which 

 has the white on the underparts extending down to the vent. 

 The other^ which may be distinguished as subsp. baicalensis, 

 has the dark colour on the underparts extending as far as in 

 Cin^lus kashmiriensis, but differs from that form as much as 

 that form does from C. melanogaster and C. aquaticus. It has 

 the head and neck paler^ the colour of these and the rest of 

 the upper parts being of a peculiar velvety mouse-brown, the 

 head and neck being rather paler than the back, and the entire 

 upper parts down to the lower rump being brown, there being 

 only a few indistinct semilunar markings on the lower rump 

 and upper tail-coverts ; the dark portion of the underparts 

 is of a dull dark earthy brown without any trace of rufous. 



In the series of Baikal specimens which 1 have examined 

 I find every intermediate stage between these two forms — 

 from subsp. baicalensis to a specimen of C. leucogaster in my 

 own collection, which has the underparts as white and the 

 head and neck as pale as in any specimen of C leucogaster 

 from Turkestan. 



I am indebted to Mr. Seebohm for an opportunity of 

 examining a large series of Dippers from Siberia, chiefly from 

 Krasnoyarsk, in his collection. All of these are identical 

 with the dark-bellied form from Lake Baikal, Taczanowski, 

 in his recently published posthumous work (Faun. Orn. Sib. 

 Orient, p. 211), recognizes only one species of White-bellied 

 Dipper in Siberia — Cinclus leucogaster; but he refers to 

 specimens with the abdomen dark, such as I describe above, 

 and considers them as intermediate forms between C. kash- 

 miriensis and C. leucogaster. He also states that he has 

 examined specimens that are intermediate between that form 

 and Cinclus sordidus, but I have never had an opportunity of 

 examining a specimen of this variety. 



The white-bellied form {Cinclus leucogaster) inhabits 

 Turkestan, Mongolia, and the countries north of Kashmir, 

 ranging into the Baikal district. I do not find that in the 

 Altai or in Turkestan it intergrades with Cinclus kashmiriensis, 

 but, as above stated, in the Baikal district typical specimens 

 of C. leucogaster are comparatively speaking rare, though I 



SER. VI. VOL. IV. 2 c 



