ScHARFF — On the Origin of the European Fauna. 429 



I. Those of the first division comprise all animals -whose origin is 

 obscure. Many of them may at some time or other have been intro- 

 duced by man, such as the rat or the mouse. The majority, however, 

 I think, are of great antiquity, and their origin dates from some remote 

 geological age. They appear to be mostly indifferent to changes of 

 temperature, and many thrive equally well in cold and in hot 

 countries. The small brown slug {AgrioUmax laevis), the Painted 

 Lady butterfly {Vanessa car did), and the bam owl {Strix flammea) are 

 familiar examples. 



II. To the animals of the second division belong those of which we 

 have distinct evidence, from their geographical range, that they are of 

 Arctic origin. As I hope to prove later on, 'they have arrived in 

 Ireland directly from the north. Among the Mammals, the reindeer, 

 which formerly inhabited this country, the Irish stoat, and the Irish 

 hare form part of this northern section. The beetles Pelophila hore- 

 alis and Blethisa midtipunctata, the butterfly Coenonympha typjion, 

 the small shell Vertigo alpestris, as well as the common stickleback 

 {Gasterosteus aculeatus) have all reached Ireland from the north. ^ 



III. The third division includes the bulk of the Irish fauna. In 

 the first place, we have to consider those animals whose birth-place 

 appears to be in South-western Europe, then we have those which 

 originated in the Souther South-central Europe, whilstthere are others 

 which came to Ireland from the south-west, though they may j)rimarily 

 have migrated there from central Asia across Southern Europe. I^o 

 very strict line can be drawn between the animals of South-central 

 and those of South-western European origin, but we may with Edward 

 Forbes (33 «, p. 12), regard the most southern as the oldest. A good 

 many of these are altogether absent from England, whilst they are 

 mostly confined to the west coast in Ireland. Taking all the Irish 

 southern types into account, we find that the majority are confined, 

 in the remainder of the British Isles, to the south-western parts of 

 England and "Wales. In some cases they appear again in the extreme 

 north of England and in Scotland without, however, being known in 

 the intermediate tracts. 



"We can sub-divide this southern fauna, therefore, into a south- 

 western and a south- central one : to the former belong the well- 

 known bullfinch [Pyrrliula europaea), the dipper {Cinclus aquaticus), 



1 Among the Irish, plants we have some species, such as Spirantlies Romanzoviana, 

 Eriocaulon septangulare and Sisyrhynchium angustifolium,v!^ic)i appear to belong to 

 the same division. 



