been met with in the caves explored since that time in Wales, and in
England as far north as Derbyshire (Creswell), proving that palaeolithic
man hunted the mammoth and rhinoceros and other extinct animals over the
whole of southern and middle England.

The discoveries in Kent's Hole and in the Creswell caves prove further
that palaeolithic man was in two stages of civilization--the ruder or
riverdrift man, with implements of the type found in the river gravels
(see ARCHAEOLOGY; and PALAEOLITHIC) being the older; and the more highly
advanced, or the cave-man, mainly characterized by the better
implements, and a singular facility in depicting animal life (as shown
by the figure of a horse incised on the fragment of a bone found in the
Creswell caves), being the newer. We may also conclude from the absence
of palaeolithic implements from the glaciated regions in which most of
these caves occur, that both riverdrift and cave-men dwelt in middle and
northern Britain in the pre-glacial age, their remains being protected
in the caverns from the denuding forces that removed all traces of their
existence from the surface of the ground in glacial and post-glacial
times. The riverdrift man is, however, proved to be post-glacial in
southern and eastern England, by the occurrence of his implements in the
river gravels of that age. Both these peoples inhabited southern England
and the continent before and after the glacial period. The riverdrift
man, whose implements occur in river deposits in middle and southern
Europe, in Africa, Palestine and Hindustan, is everywhere in the same
age of primitive barbarism, and has not as yet been identified with any
living race. The cave-men are in a higher and more advanced stage, and
led a life in Europe identical with that of the Eskimos in the Arctic
regions.

_The Pleistocene Caves of the European Continent._--The researches of
Mortillet have proved that the same two groups of cave-dwellers occur in
the caves of France, the older being represented by the Chelleen and
Mousterien sections, and the newer by that of Solutre and La Madelaine.
To the former belong the human remains found in the caverns of Spy and
Neanderthal, which prove that the riverdrift man had "the most brutal of
all known human skulls." To the latter we must assign all the caves and
rock-shelters of Perigord, with the better implements, explored by
Lartet and Christy in 1863-1864 in the valleys of the Vezere and
Dordogne.