Dr. N. SevertzofF on the Mammals of Turkestan. 335 



(if C. shyn is identical with it), which has a very extended 

 range ; but should 0. sibirica and G. shyn form two distinct 

 species, then the localities inhabited by them will be separated 

 by the Narin, as far as can be fixed now ; perhaps the limit 

 might also be formed by the plains of Aksay and Chatir-kul. 

 Ovis argali was also looked upon as being an exception to 

 the above rule ; but, as I showed above, this supposition 

 arose only from the confusion of several of the Central- Asiatic 

 sheep with this species ; this is another reason which induces 

 me to believe that Gapra skyn is distinct from G. sibirica. 



According to the analogy of the sheep, I suppose that there 

 are even more than two species of Gapra inhabiting the Thian- 

 Shan ; this, however, yet remains to be proved. If we com- 

 pare the limited range of each species of the Capridee with the 

 much larger distribution of other mountain-mammals (as, for 

 instance, Gapella rupricapra^ whose range extends from the 

 Pyrenees to the Caucasus, or the Oreotragus saltator^ which is 

 to be found from the Cape of Good Hope upwards to Abyssinia), 

 we shall find that a limited distribution is not at all a general 

 characteristic of mountain-mammals. Nor is it dependent 

 upon the physical conditions, particularly in the mountains 

 of Central Asia, all of which are situated near to each other ; 

 and consequently there must have been another reason for the 

 development of so many different species. This reason is to 

 be found in the change of the life of wild animals from the 

 time Avhen they were driven out from their native localities by 

 the tame flocks. In that way the habitats of wild animals 

 were separated from each other by some valleys or meadows, 

 or even mountain-plains, on which the tame ones were feeding; 

 and this separation of course has favoured the quicker develop- 

 ment of the different species. 



At the present time the wild mammals live close to the 

 tame cattle, and have adapted themselves to the conditions of 

 their life, and have got into the habit of avoiding and getting 

 away from the danger; and at the same time they have 

 learned to make use of every convenient opportunity for en- 

 larging their feeding-localities. This they could not possibly 

 have learned at once, but in the course of several generations, 

 and is the result of their increase in numbers in the localities 

 to which they were obliged to withdraw. I made the obser- 

 vation on Otis tarda, that it leaves at once those steppes in 

 which cultivation has commenced, and withdraws to such as 

 are yet uninhabited ; but the increase in their numbers on the 

 latter compels them to go back again to the localities they had 

 left, and in consequence thereof to alter their habits. The 

 same may also have been the case with the wild Capridas. 



