Clure Island Survey — Mammalia* 17 1 o 



that eveu the peculiar Irish Hare, which is, with the Irish Stoat, the oldest 

 member of our fauna, existed during the glaciation in a region now occupied 

 by the present English Channel. 



The Irish Stoat, Irish Hare, and other Mammals probably made their entry 

 into Ireland from England across a narrow land-bridge lying between Bardsey 

 Island and Wicklow at some time subsequent to their arrival in England from 

 the Continent. 



This bridge was of short duration, and was not discovered by all the 

 English mammals, some of which reached the south of England, perhaps by 

 a second continental land-bridge, in such a recent period as not yet to have 

 had time to spread over the whole country. 



There may have been a region of survival in the north and west of Scotland 

 with a greatly increased land area extending to continental Europe some- 

 where north of the Dogger Bank. This area may have been cut off for a time 

 from parts of England, as shown by the fact that in some cases the mammals 

 inhabiting it are subspecifically distinct from those of southern England 

 (e.g. the genus Microtus), A barrier appears to have cut off Scotland also from 

 Ireland, with which its fauna has no connexion. Thus Scotland may have been 

 an important centre of survival, and, having regard to its greater proximity to 

 the sea, its climate must certainly have been milder than that of Skandinavia, 

 so that the suggestion that the movement of mammals was from Scotland 

 to Skandinavia and not in the reverse direction is cpiite worthy of serious 

 consideration. 



Note on a supposed American Facies of the Ieish Mammal-Fauna. 



A number of indigenous Irish Mammals are represented in North America, 

 the following thirteen living or extinct genera being certainly common to 

 both countries : — Sorex, Myotis, Pipistrellus. Lepus, Vulpes, Canis, Ursus, 

 Martes, Mustek, Lutra, Cervus, Bangifer, Elephas. Two Irish genera 

 are, in addition, represented by closely allied genera in North America, 

 e.g. Plecotus by Corynorhinus (very closely allied), and Meles by Taxidea. 

 I have not put down the corresponding Irish and North American species, 

 inasmuch as a detailed comparison of them has yet to be made. They 

 undoubtedly vary in the closeness of their affinities; but one or two at 

 least, e.g., Sorex minutus and the North American S. richardsoni, also Myotis 

 davientoni and the North American M. carissima, are very closely related 

 indeed. 



An attempt has sometimes been made to account for the relationships 

 between the two faunas by a recent land-bridge across the Atlantic ; but it 



R.I.A. PROC, VOL. XXXI. C 17 



