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



of the long-tailed races of sheep, which, however, are known 

 to me only from descri})tions. The development of these fat 

 tails depends principally upon the salt plants on which the 

 animal feeds ; from the want of this food the tail becomes 

 smaller. It is, however, an hereditary character ; and even 

 newly bom lambs occasionally possess such a tail. The horn- 

 less sheep as a rule have also the largest fat tails. 



The changes of the tail from the change of food do not take 

 place at once: they can be more easily appreciated on comparing 

 the long-tailed sheep, which feed on salt plants in the country 

 about the Syr-Darja, with the short-tailed Kirgies sheep from 

 Karkara, which hardly ever feed on such herbs. When sheep 

 that had been feeding on salt ground are driven on more 

 nutritious meadows (not quite so salt as the former) they at 

 first begin to get fatter, and only later on the tail commences 

 to grow too. This is regularly done in the Ural and the west 

 of Liberia, where the sheep are principally sold for the sake of 

 the tallow. But if fed on plants without any salt substance in 

 them, the sheep themselves get fatter, but the tail does not 

 grow at all. 



The colour of these sheep is very variable ; there are white, 

 grey, black, and blackish-brown, or even greyish-brown indi- 

 viduals, these latter being nearest in colour to the wild species. 

 I also noticed that the belly in the dark animals is usually 

 darker than the back, like Ovis argali^ sometimes of the same 

 colour, but never lighter, like O. Polii^ O. Kardini^ or 0. 

 nigrimontana. At the same time the last-named species is 

 nearest to the tame sheep in an indirect way, viz. by its 

 partial resemblances to and differences from O. Polii. In 

 examining the tame sheep of Arabia, Ruppell has recog- 

 nized their distinction from the European long-tailed sheep, 

 and thought that they originally descended from O. argali^ 

 having only altered by domestication. A. Brehm, mentioning 

 this supposition of Riippell's (' Ergebnisse einer Reise nach 

 Habesch '), agrees Avith him regarding these sheep's specific 

 distinction, but thinks itdoubtful that they can be descended from 

 0. argali, which differs so much in size from the tame breed. 

 Brehm did not analyze the character or value of these differ- 

 ences as compared with the points of resemblance between the 

 tame sheep and 0. argali] but the latter are of weight and 

 will prove Riippell's statement to be correct. Of all the 

 wild sheep, 0. argali is most certainly the nearest to the 

 tame ones ; notwithstanding those characters which it has 

 in common with its wild relatives, it approaches the tame 

 sheep in two veiy important points, viz. in the shortened 

 chords of the basal curve of the horns and in its colour. 



