The Alpine fauna and also the flora are made up of a number of elements, the eastern one being the oldest. The latter is represented in the Alps by the older and newer Oriental migration. The general range of the Alpine Steinbock, Chamois, Marmot, Vole, Shrew, and Hare are specially referred to. The Alpine birds are few in number, and all of them are readily traceable to an Asiatic ancestry. Among the Amphibia, the Salamanders are considered of Alpine origin.
Dr. Kobelt tells us that a uniformity of character marks the Alpine molluscan fauna. _Campylaea_,--often considered a sub-genus of _Helix_,--_Pomatias_, _Zonites_, are looked upon as truly Alpine genera. For very long periods the Alps seem to have received no addition to their molluscan fauna from other areas. The case is very different with the _Lepidoptera_, some of the most striking species being evidently Asiatic immigrants. Some examples of _Coleoptera_ and _Orthoptera_ are mentioned, and their origin discussed.
We find as the result of these considerations that the majority of the Alpine species are either indigenous or have come from Asia with the Oriental migration. None of the northern or western immigrants appear to be among the characteristic Alpine species, and it seems that the Siberian migrants have not retired to the Alps, as some naturalists have been led to suppose. It is evident that the fauna must have survived the Glacial period on the Alps, though according to geological evidence glaciers of enormous size originated on these mountains.
The identity of many Alpine species with Scandinavian ones appears at first sight due to a direct migration from the Alps to Scandinavia or _vice versâ_. Perhaps such a migration has taken place to some extent, but it is probable that from a Central Asiatic centre some species spread across Arctic America into Northern Europe, and also westward to the Alps. The Grouse family forms an interesting example.
There are two older theories which explain the similarity between the Scandinavian and Alpine faunas. Forbes's view, which gained most adherents among naturalists, was that the Scandinavian and Alpine animals were driven into the plain by the cold during the Glacial period, and when they ultimately regained their homes, some individuals of the northern species moved southward, and a few of the southern ones northward. By the more recent theory of Nehring, the Siberian animals which invaded our continent from the east, and then spread northward to Scandinavia and southward to the Alps, formed the nucleus of the faunas of these two areas. The objections to both of these views are fully set forth in this chapter.