THE GEOLOGY OF KOLGUEV 395 



conditions of the interior of the island— is a sufficient index to the 

 growth of Kolguev as a whole. 



If the question should further be asked, ' How, and from where, then, 

 has this debris come ? ' I think for answer one may safely say as much 

 as this : — partly by some great river system, and partly by the ice. The 

 granite, sandstone and limestone (?) boulders found on Kolguev are 

 almost certainly ice-borne erratics from the mainland tundra and 

 Novaya Zemblya. Such a striking sandstone as that figured here, 

 which, lying now between the snow-banks, shows round its side striations 

 made by ice, may safely have come from the tundra, where no traveller 

 can fail to be struck with the sand-rocks which take there similar 

 eccentric shapes from the wearing of such forces long ago. But at least 

 some fossils in my collection taken from boulders on Kolguev seem to 

 point to a more distant source as kindly described for me by Mr. 

 Ethridge. They belong to the Upper Silurian period. Two are corals. 

 Halysites catenularius and Cyathophylhim truncatum. One is a 

 gasteropod, probably Naticopsis. 



Note. — I have ventured to incorporate with this part of a paper read before the 

 Royal Geographical Society, an abstract of which appeared in The Geographical 

 Journal Tor February 1895. 



