Notable Quaternary forms (now extinct) on the American continent are the gigantic sloth-like animals Megatherium, which reached eighteen feet in length, and Mylodon, one species of which (M. robustus) was eleven feet in length; Armadillos, such as Glyptodon, with a total length of nine feet; Chlamydotherium, as big as a rhinoceros; and Pachytherium, equalling an ox.
In Australia we find marsupial forms as at the present day; but they were gigantic in comparison with the latter. As for example, the Diprotodon, which equalled in size a hippopotamus, and the Nototherium, as large as a bullock.
I may mention a few other species, the remains of which are associated with some of those commented on in the last few pages; but which, as they have undoubtedly continued in existence down to the present period, are external to the present portion of my argument, and are either treated of elsewhere, or need only to be referred to in a few words.
Fig. 14.—Mylodon robustus. (After Figuier.)
It must also be borne in mind that the linking together of species by the discovery of intermediate graduated forms, is daily proceeding; so that some even of those spoken of in greater detail may shortly be generally recognised, as at present they are held by a few, to be identical with existing forms.
The Hippopotamus.—The Hippopotamus major, now considered identical with the larger of the two African species—H. amphibia, has been found associated with E. antiquus and R. hemitæchus of Falc in Durdham Down and Kirkdale caves, and in those at Kent’s Hole and Ravenscliff. It has also been found in river gravels at Grays, Ilford, and elsewhere, in the lower part of the river-border deposits of Amiens with flint implements, and in Quaternary deposits on the continent of Europe.
The Cave-Lion—Felis spelæa—is now considered to be merely a variety of the African lion (Felis leo), although of larger size; it had a very wide range over Britain and Europe during the Post Pliocene period, as also did the leopard (F. pardus) and probably the lynx (Lyncus).
The Reindeer or Cariboo—Cervus tarandus—which still exists, both domesticated and wild, in northern Europe and America, is adapted for northern latitudes. It formerly extended over Europe, and in the British Isles probably survived in the north of Scotland until the twelfth century.
Its remains have been found in Pleistocene deposits in numerous localities, but most abundantly in those which M. Lartet has assigned to the period which he calls the Reindeer age.