Among the extinct beasts, were some of very remarkable character. There were two or more species of elephant, which seem in this age to have overspread, in vast herds, all the plains of Northern Europe and Asia; and one of which we know, from the perfect specimen found embedded in the frozen soil of Siberia, lived till a very modern period; and was clothed with long hair and fur, fitting it for a cold climate. There were also three or four species of rhinoceros, one of which at least (the _R. Tichorhinus_) was clad with wool like the great Siberian mammoth. With these was a huge hippopotamus (_H. major_), whose head-quarters would, however, seem to have been farther south then England, or which perhaps inhabited chiefly the swamps along the large rivers running through areas now under the sea. The occurrence of such an animal shows an abundant vegetation, and a climate so mild, that the rivers were not covered with heavy ice in winter; for the supposition that this old hippopotamus was a migratory animal seems very unlikely. Another animal of this time, was the magnificent deer, known as the Irish elk; and which perhaps had its principal abode on the great plain which is now the Irish Sea. The terrible machairodus, or cymetar-toothed tiger, was continued from the Pliocene; and in addition to species of bear still living, there was a species of gigantic size, probably now extinct, the cave bear. Evidences are accumulating, to show that all or nearly all these survived until the human period.