The geographical distribution of animals, with a study of the relations ...

;chat, vi.] MAMMALIA OF THE OLD WORLD. 113A more interesting fact for us is the occurrence of the genusTapirus in the Newer Pliocene of France and in the older bedsof both France and England, since this genus is now isolatedin the remotest parts of the eastern and western tropics. Thegenera Rhinoceros, Hippopotamus, and Sus, occur here asin thepreceding epoch.We next come to the deer genus {Cervus), which appears tohave been at its maximum in this period, no less than eightspecies occurring in the Norwich Crag, and Forest-beds. Amongthe Bovidae, the antelopes, ox, and bison, are the only forms representedhere, as in the Post- Pliocene period. Passing on to theProboscidea, we find three species of elephants and two of Mastodonpreserved in European beds of this period, all distinct fromthose of Post-Pliocene times.Rodentia.—In this order we find representatives of manyliving European forms ; as Cricetus (hamster), Arvicola (vole),Castor (beaver), Arctomys (marmot), Hystrix (porcupine),Lepus (hare), and Lagomys (pika) ; and a few that are extinct,the most important being Chalicomys, allied to the beaverand Issiodromys, said to come nearest to the remarkablePedetes of South Africa, both found in the Pliocene formationsof France.General Conclusions as to Pliocene and Post-Pliocene Faunas ofEurope.—This completes the series of fossil forms of the Pliocenedeposits of Europe. They show us that the presence of numerouslarge carnivora and ungulates (now almost wholly tropical) inthe Post- Pliocene period, was due to no exceptional or temporarycause, but was the result of a natural succession from similarraces which had inhabited the same countries for long precedingages. In order to understand the vast periods of time coveredbv the Pliocene and Post-Pliocene formations, the works of SirCharles Lyell must be studied. We shall then come to see, thatthe present condition of the fauna of Europe is wholly new andexceptional. For a long succession of ages, various* forms ofmonkeys, hyaenas, lions, horses, hipparions, tapirs, rhinoceroses,hippopotami, elephants, mastodons, deer, and antelopes, together