THE BIRDS OF MONGOLIA ETC. 139 



from the neighbouring mountains. They build their nests on the inaccessible 

 rocks of Mongolia and Kan-su; and I saw in one of these nests, in the 

 beginning of June, in the Suma-had mountains, a good-sized young bird. 

 Close to this there was also a nest belonging to a pair of Ravens, who, in the 

 absence of the old Vultures, stole the food from the young one. As is well 

 known, these Vultures pass the night usually on some rock or cliff, which 

 they regularly use for a very considerable time. Such resting-places can 

 easily be discovered by the large amount of white guano, which can be seen 

 a long way off. In the morning this bird does not appear to leave its resting- 

 place before 7 o'clock ; at least, we never saw one flying earlier. During the 

 day they frequently sit near some brook, in order to drink or bathe. 



On comparing my specimens with others from the Caucasus and the 

 Altai, now in the Museum of the Academy of Sciences of St. Petersburg, I 

 did not detect any difference in the plumage. 



Measurements : — 





Length. 



Width. 



Wing. 



Tail. 



Culmen. 



Tarsu 





in. 



in. 



in. 



in. 



in. 



in. 



J, from Mongolia . 



. 46 



102 



33 



21-5 



403 



3-8 



d, from Kan-su 



. 44 



97 



33 



23-5 



? 



? 



2. VuLTUR MONACHus, L. Gviff Mouach, 



Like the preceding species, Vultur monachus inhabits Mongolia, with the 

 exception of the northern parts of it ; it is also found in Northern Tibet, 

 but is very rare in Kan-su, and is replaced there by the succeeding one. 

 Its habits are the same as in the other allied species. 



For almost whole days this Vulture describes circles so high in the air 

 that it cannot be seen by the naked eye. Nevertheless the bird can see, even 

 from such an altitude, what is going on below ; and having observed some 

 carrion, round which there usually assemble great numbers of Magpies, 

 Ravens, and Kites, it contracts its wings at once, and like a bomb drops from 

 the air on its prey. After the arrival of the first one, others follow in quick 



u 2 



