Note 342 — Chapter IX

Frequently these implements have been found, in sufficiently deep beds, beside bones of the straight-tusked elephant (Elephas antiquus), the smooth-skinned, two-horned rhinoceros (Rhinoceros Merckii), the great hippopotamus—that is to say, of animals characteristic of the first interglacial period. As these species are allied to the elephant, the rhinoceros, and the hippopotamus of Africa of the present day, the hypothesis has been propounded that they came from this continent, utilising the numerous isthmuses then existing (between Gibraltar and Morocco, between Sicily, Malta and Tunis, etc.). Man, the maker of the Chellean implements, followed, it is supposed, in their steps. One might argue with equal force that the migration took place in the opposite direction.