Dr. N. Severtzoff on the Mammals of Turkestan. 331 



O. argali, like all tame Turkestan sheep, has the belly darker 

 than the back — a peculiarity analogous, to a certain extent, to 

 the black cross bands on the wings of the dovecot pigeon, to 

 which so much importance is attached by Mr. Darwin as 

 proving that the origin of that bird is to be sought in Golumba 

 lima. Also the horns of O. argali are close to the sides of 

 the skull in proportion to their large size, this being the only 

 species of all wild sheep in which this is the case. 



Consequently the only difference consists in the larger size 

 of the animal and the proportionally larger horns. Here a 

 suggestive analogy is afforded by O. nigrimontana^ which in 

 its general appearance and colour partly resembles O. Poliiy 

 but is considerably smaller in size, and lives at a much lower 

 elevation. It seems a very reasonable hypothesis that the 

 wild stock of the tame sheep of Turkestan was or is very much 

 like O. argalij only of a smaller size and with smaller horns, 

 inhabiting the low mountains of Mongolia, a locality which 

 is so very little known that a species like the one suggested 

 may possibly yet be found there. If not, wliat is more likely 

 still, it may be taken for granted that this species is extinct 

 in the wild state, in the same way as the original of our long- 

 tailed European sheep is not now to be found. 



If the wild sheep, the original of the fat-tailed breed, was 

 nearer to the present tame one than to 0. argah\ its increase 

 in the tame state very likely drove the wild ones from their 

 original grazing-places ; and these latter not being admitted 

 by the larger wild sheep into the higher mountains, were 

 gradually exterminated. 



It is also probable that the smaller sheep were more easily 

 tamed than the larger and stronger species, and would not 

 only be more suitable for domestication, but, on account of 

 their being more easily captured, they were more pursued by 

 the sportsman, which is another reason for the extinction of 

 this species ; the principal cause of this latter, however, was 

 probably the occupation of its feeding-grounds by the tame 

 herds. 



But another question arises here — namely, whether 0. argali 

 as it is now existed at the time when the original stock of the 

 present Kirgies sheep was first tamed ; for this domestication 

 would of course have some influence also on the wild breeds. 



At the present time the wild sheep are driven out of the 

 meadows which they occupied formerly, and which now are 

 exclusively the pastures of the tame flocks ; and many changes 

 in the wild beasts find an explanation in this. 



Whilst the tame sheep were undergoing alteration according 

 to the wants of men by means ofbrecfling from selected speci- 



