appeared from their former habitats, leaving their carcases to tell the tales of their struggles. Some of them have become extinct, and others have betaken themselves to more congenial climates, according as they possessed northern or southern proclivities. Man was the contemporary of all these animals, and he is now the most conspicuous among the survivals who successfully battled against the adverse circumstances then prevalent in Europe.
Caves.
Human bones are not often found in the river-drift gravels, for the simple reasons that they were not numerous to begin with, and that being small, they have mostly disappeared by the ordinary process of decay. There is, however, another source of evidence which has yielded a large number of skulls and other portions of human skeletons, viz., the caves and rock-shelters which served as occasional retreats for the nomadic people who inhabited Europe during the lower and middle stages of the Pleistocene period.
The evidential materials disinterred from these localities are much more varied than those of the river-drift gravels, as they contain, in addition to the bones of man and the Pleistocene mammalia, a number of tools, weapons, and ornaments, together with food refuse, and other indications of the kind of social life prevalent among the people of those days. Many of the contemporary carnivorous animals, especially hyænas and cave-bears, frequented these caverns, and, like man, introduced into their interior recesses portions of the animals captured outside, there to be consumed in peace and security—thus accounting for the presence of bones of the mammoth, reindeer, horse, bovidæ, etc., in places absolutely inaccessible to those animals in a state of life. Caverns containing remains of human skeletons, or specimens of his handicraft works, associated with bones of the extinct mammalia are widely distributed, being found, more or less, in England, France, Belgium, Switzerland, Germany, Austria, Italy, Spain, and Portugal; but it is a significant fact that they are generally wanting in those countries which had not been inhabited till after the retreat of the mer de glace, such as North Britain, Scandinavia, and
