Page:The Zoologist, 3rd series, vol 1 (1877).djvu/147



account of the quadrupeds which frequented the British Islands in bygone ages and before historic times would be imperfect without a brief allusion to the physical conditions of the country during the period of their existence. My observations on that head, however, will be confined to the vast epoch which has elapsed since the close of what is known as the glacial period, when Europe was emerging from the white sheet which for unreckoned ages had clad it, from the Pole to the Mediterranean, in ice and snow. The proofs of this curious episode in the history of the earth are as clear as is the existence of glaciers at the present day. It is, moreover, evident, that the cold period came on suddenly, and, as regards the British Islands, at a time when the physical aspect of the country—at least, as regards the main features of the landscape—did not materially differ from what is now observed. The land was then inhabited by quadrupeds, some of which were identical with species now living, although many afterwards became extinct, and did not reappear. This has been named the pre-glacial period, when our climate was perhaps somewhat milder than it is at