472 Proceedings of the Royal Irish Academy. 



across the old Bekring Sea connexion. It could not have come from 

 Asia before the European hare, as I have clearly demonstrated (p. 453) 

 that a barrier kept back the Siberian fauna. The only way it could 

 have entered Europe is from the north, its original home. I shall 

 bring for^ivard evidence to show that Scandinavia and Spitsbergen, 

 were connected before and during the Glacial Period (see also page 462). 

 I believe that the Arctic hare migrated along that land to Scandinavia, 

 and then to Scotland and Ireland, which were at that time all united, 

 that is to say, in pre-Forest-bed times, when Scandinavia, as I have 

 mentioned, was not directly connected with continental Europe (see 

 map, p. 461). It then spread into England, where its remains were 

 found in the Mendip Hill Cave (not in any true Pleistocene deposits) 

 and subsequently to the Pyrenees and Alps. 



JIustela erminea. — The well-known fact that the stoat, like the 

 Arctic hare, generally changes its fur to white iu winter, is suggestive 

 of a nortliern origin. Even in Ireland both species often become 

 partially white in the winter months, though there may be little 

 or no snow on the ground. 



Its absence from the Mediterranean region and from Portugal and 

 Southern Spain proves, that it did not enter Europe from the south. 

 "We have learnt (p. 447), that the stoat came with the weasel and pole- 

 cat from Siberia, and with them invaded England, after having 

 traversed the central plain of Europe, but, as I have stated before, I 

 consider it improbable that, of the Siberian immigrants, it almost alone 

 should have reached Ireland. Still the stoat undoubtedly did migi'ate to 

 Ireland. "When we consider, however, that the Irish stoat is very dis- 

 tinct from the ordinary English and continental form, so much so, that 

 Messrs. Thomas and Barrett-Hamilton have recently raised it to the 

 rank of a distinct species (86), the view that it belongs to a different 

 migration will perhaps be more readily accepted. The stoat is certainly 

 of northern origin, and it is one of the few Mammals which still 

 inhabits the Arctic regions. It has been observed in Grinnel Land, 

 Greenland and Spitsbergen, so that provided a land-passage existed 

 connecting the latter with Scandinavia, it could easily have entered 

 Europe direct from the north. It spread from the Ai'ctic regions to 

 North America, and from there into Asia, being still found on the 

 islands of the Aleutian chain (36) which used to form the highway 

 between the two continents. A branch of the Asiatic stock even pene- 

 trated into Xorthem Africa (85), possibly by way of Greece and 

 Southern Italy, though not found in Southern Europe at present. 

 But this Algerian form is. as Mr. Oldfield Thomas mentioned to me. 



