Bevieivs — Scharff's Origin of the European Fauna. 473 



recent origin, and it has only spread from its original home, which 

 may be in the Alps, after Ireland was already disconnected from 

 Great Britain. It has never reached Scotland, Spain, Norway, 

 Russia, Greece, or any of the Mediterranean islands, except Sicily, 

 where it is present, according to Doederlein. Then there are forms 

 which, though they have come to the British Islands from Southern 

 Euroj)e, have probably not originated there, but in Central or 

 Southern Asia. Certain of these Asiatic species have joined what 

 I call this ' Southern Migration,' but subsequently they have 

 invaded Europe along with the Siberian Migration. In most of 

 these instances, however, the members of the earlier Southern 

 Migration belong to a different variety from those of the later 

 ones, or exhibit such racial characters, that naturalists are able to 

 distinguish them from one another, and thus differentiate between 

 the two migrations " (p. 480). The author cites two such cases, 

 namely, those of the European hare and the bullfinch. 



Insular Mollusca. — " The moUusca of islands are of great impor- 

 tance in studying geographical distribution. A knowledge of the 

 mollusca of such islands as Ireland, Sardinia, and Corsica, will help 

 us to solve many of the problems associated with their former con- 

 tinental connections. Especially is this the case with the slugs. 

 As the sea forms an impassable barrier to slugs, being deadly both 

 to themselves and their eggs, the occurrence of the same species on 

 an island and the adjoining mainland proves that these were formerly 

 connected by land." 



" The great genus Arion undoubtedly had its origin in South- 

 Western Europe. Most of the species are still confined to the 

 Spanish Peninsula ; and if we proceed south, east, or north, the 

 number of species gradually decreases, and outside Europe and 

 Northern Africa the genus is quite unknown." (p. 480.) 



Bange of the Bed Deer [Cervus elaphus) and its varieties. — "The 

 red deer as a species has probably reached Ireland from South- 

 western Europe. Not that I would place its centre of origin in 

 that part of the world, for it almost certainly originated in Asia, 

 but that geographical conditions at the time of its migrations to 

 Europe were such that it had no proper means of spreading over 

 the central and northern portions except from that particular 

 region. 



" In tracing the present range of the red deer, we have to bear 

 in mind that there are a number of forms very closely allied to 

 Cervus elaphus, viz., C. Canadensis, C- maral, C. Corsicanus, 

 C. harbarus, C. Gashmerianus, C. affinis, C. eustephanus, and C. xan- 

 thopygiis. Sir Victor Brooke has already referred to the fact that 

 the antlers of C. eustephanus cannot be distinguished from those 

 of C. Canadensis. A great similarity is said by Professor Nehring 

 to exist between many of the antlers found in European Post-Glacial 

 deposits and the recent antlers of C. Canadensis ; and he is inclined 

 to refer them, along with the large-antlered Asiatic C. eustephanus, 

 C. xanthopygus, etc., to the same species, and with this view Pro- 

 fessor Woidrich agrees. Then, again, G. maral is looked upon as 



