Only one species of the well-known Polar genus _Œneis_, viz. _Œ. aëllo_ occurs in the Alps. It has always been taken at very high elevations near the verge of the snow-line on the most lofty parts of the Simplon Pass, and other similar situations. Altogether about a dozen species of this genus of butterfly are known, most of which are confined to the polar regions of the Old World and the New, though some have found their way to the extreme south end of South America, in what manner is still a mystery. Like the preceding genera, this also appears to have emerged from Central Asia. The genus, too, is closely allied to the last, and though its range is not quite so extensive, it resembles it in many respects. The Alpine species of _Œneis_ came to Europe by the Oriental route. But the Lapland species--at any rate _Œ. jutta_ and _Œ. bore_--have taken a somewhat circuitous route to reach our continent. They first migrated from Asia to North America, and then by the old land-connections by way of Greenland to Lapland. It is noteworthy that Professor Engler felt convinced (cf. p. 171) that the occurrence of many of the Arctic plants in North Scandinavia and Siberia could be best explained by the assumption of such a migration from Asia _viâ_ North America to Europe rather than by the shorter route. There are far more Alpine beetles than butterflies, but their geographical distribution is less well known, and it is therefore not at all safe to base important conclusions as to the origin of a fauna on that group alone; however, as far as my limited knowledge of the _Coleoptera_ of the Alps goes, their general range seems to agree perfectly with other orders of insects. Many can also be traced to an Asiatic home, and the route they came by is the Oriental and not what I have called the Siberian. Take, for instance, the genus _Nebria_, of which we have one species in England--a black insect with a bright reddish-yellow border and long light legs--known as _N. livida_. There are about eighty European species, most of which are confined to the Alps, the Caucasus, the Pyrenees, Spain, and Greece. The genus, however, ranges all over the Holarctic Region, that is to say roughly, over Europe, Central and Northern Asia, and North America. The centre of distribution lies in Central Asia. If the genus had poured into Europe by the northern or Siberian route, we should probably now find many species in Northern Russia, Germany, and France; but this is not the case, and we may therefore assume with some justification that the Southern or Oriental route was the only one available at the time when the bulk of the species of _Nebria_ wandered to Europe. Many of the _Nebrias_ occur in Switzerland and in the Alps, generally on the margins of the snow-fields and glaciers, like _N. Germari_ and _Brunii_. Others, for example, _N. atrata_, ascend to the highest limit of animal life, having been observed at a height of over 10,000 feet.