THE BIRDS OF MONGOLIA ETC. 197 



the mountains, and is tolerably common. Its song in spring is very pleasant, 

 and exactly like that of our Song-Thrush. We found two nests in the middle 

 of May : one was constructed on the broken stump of a tree, and the other 

 on the branch of a willow ; both were about seven feet from the ground. In 

 the former there were four, and in the latter two eggs Can incomplete set). 

 These are quite different from those of T. musicus, being rounder, and 

 marked on a dull reddish- white or whitish-grey ground with irregular brown 

 and pale reddish-brown spots and streaks. The larger diameter measures 

 l^^-02-l"-08, the smaller 0''76-0'^-84 ! 



The first fledged young we observed on the 30th of June. 



Measurements : — 



Lengtli. Widtli. W^ing. Tail. Culmen. Tarsus, 



in. in. in. in. in. in. 



6 . 



9-5 



14-5 



4-74 



3-86 



0-67 



1-4 



9 . 



. 10 



13-7 



4-65 



3-93 



0-7 



1-4 



108. TuRDUS RUFicoLLis, Pall. Drost crasnosohoy. 



With the exception of Halka and Northern Tibet, this bird was observed 

 by us wherever we went during its migration, and appears to be the 

 most numerous migrant of all the Thrushes. At Tsaidam we observed the 

 first birds on the 14th of February ; but in Kan-su and Muni-ul the principal 

 migration took place in the middle of April. In autumn it was rather 

 common in the Ala-shan mountains ; and at the same time we observed them 

 in Kan-su, but not so numerous as in spring ; and on the 5th of November 

 we saw the last few specimens south of Koko-nor, 



I have in my collection about ten specimens of T. ruficollis. They all 

 differ from T. naumanm by their grey flanks and the sharply marked red 

 colour of the throat and crop, which (according to age) varies from light 

 brick-red to chocolate-colour. 



We have not noticed this bird in Ussuri country. 



