352 The American Geologist. December, i898 
western Europe appear to have there exterminated most of 
the species of large mammals already mentioned, through 
persistently hunting them for food, so that at last this peo- 
ple, destitute of metals, but skillful in making implements of 
stone, bone, and horn, and having even a high artistic taste 
in carving figures of animals on horn and ivory, became 
mainly restricted, in providing food, to the sea borders, liv- 
ing in the greatest numbers in Denmark, and subsisting on 
smaller game, fish, and especially littoral marine mollusks, 
whose shells form the principal mass of the very remarkable 
kjokkenmoddings (kitchen-middens) of the Danish coasts. 
About the time of the recession of the ice-sheet from the 
Mecklenburg or Baltic moraines, described by the sixth paper 
of this series, another race or group of peoples, more advanced 
toward civilization, having attained the art of polishing their 
stone implements, tending herds and practising agriculture in 
some degree, and bringing with them domestic animals and 
cultivated plants derived from wild species in the fauna and 
flora of western central Asia, immigrated and took possession 
of Europe, supplanting and probably mainly exterminating 
the old Palaeolithic .people. This great immigration, ending 
the Palaeolithic and inau^gurating the Neolithic period, was 
probably the dispersal of the Aryans, who, as shown by the 
researches of philologists, carried throughout Europe lang- 
uages of close' affinity with those which at the same time or 
partly later spread also through Persia and India. 
The men of the Somme gravel deposits belonged, if I 
rightly interpret the geologic record, to the early part of the 
Glacial period, previous to its culmination; the inhabitants of 
the caverns of Dordogne, in southwestern France, possessing 
greater skill in the manufacture of flipt implements and adding 
others of bone and horn, hunting herds of wild horses and 
reindeer, seem correlative with the maximum stage of glacia- 
tion; and later these people spread northward, following the 
retreating ice-sheet to the boundary of its Mecklenburgian 
stage. De Mortillet and Cartailhac, as archaeolgists, divide 
the Palaeolithic period of France into four epochs or stages, 
succeeding one another as follows: i, Acheulian, named from 
St. Acheul (or Chellean, from Chelles near Paris); 2, Mouste- 
rian, from Le Moustier in Dordogne; 3, Solutrian, from So- 
