175 





Mr. Kirwan, in speaking of the shells in the deserts 

 of Naryn and others more southern, between the Wol- 

 ga and the Jaik or Ural, says, " The shells which 

 abound in this extensive flat, exactly resemble those of 

 the Caspian, and are different from those of the adja- 

 cent rivers."* 



To what shall we look for the cause of these exten- 

 sive deposites of fossil shells, that are peculiar to the 

 Caspian sea, whilst nothing of the kind has ever been 

 observed, that I can find, either on the west, the south, 

 or the east side of it? If that sea has receded, as is 

 pretended, or fallen below its ancient level, we might 

 reasonably expect to find fossil shells, once peculiar to 

 it, on all its borders, except where rocks exist ; but 

 this is not the case. Whilst they abound in the banks, 

 and in the neighbourhood of the Wolga, no mention 

 is made of any thing of the kind near the mouth of the 

 Oxus, or in its ancient course ; neither do I find any 

 thing of the kind, as having been observed in the great 

 desert between the Caspian sea, and the sea of Aral. 



That they were carried there by currents from the 

 south, and deposited, is rendered still more probable, 

 from the circumstance that in the same districts, the fos- 

 sil remains of the elephant, &c. are found buried in the 

 alluvion,! which is many degrees further to the north, 

 than the countries to which they naturally belong, or 

 which they have ever been known to frequent. 



* Kirwan's Essays, page 91. 



t See Pallas's Travels, volume I, page 108 and 115. 



