Primitive Man in the Sotmne Valley. — Upham. 359 
that the infrequent implements found in the upper series are 
of the later developed Mousterian type. 
We may infer, additionally, that while the still later So- 
lutrian and Magdalenian types of implements were being de- 
veloped, in the progress of the Palaeolithic period, more mod- 
erate climatic conditions prevailed in northern France, with 
no important contribution to the valley gravels. These three- 
fold deposits therefore appear referable to early stages of the 
Ice age, probably the Albertan, Kansan, and Illinoian, or 
rather to the European representatives of these stages. Dur- 
ing the very long interval that ensued, previous to the lowan 
or Polandian readvance of glaciation, the Palaeolithic men 
of western Europe passed through their Solutrian and Mag- 
dalenian stages; and shortly afterward, about the time of for- 
mation of the Wisconsin or Mecklenburg moraines, these 
men, destitute of metals, of agriculture, or of domestic ani- 
mals, were practically crowded ofif from Europe, famished bv 
extinction of the large species of game, and driven out, ex- 
terminated, or absorbed, by the immigrating- Neolithic peo- 
ple. The invaders, as before noticed, though ignorant of the 
most useful metals, brought wheat and barley, cattle, sheep, 
goats, and swine, and, most significant in linking them with 
later written history, the Indo-European languages. Their 
arrival and settlement, and the end of the Palaeolithic period, 
preceded the departure of the ice-sheet from Scotland and 
Scandinavia, where no Palaeolithic types of stone implements 
are found, although Neolithic types abound and are collected 
in immense numbers. 
Sections of the Somme gravels at Menchccourt, Mautort. 
and other localities near and below Abbeville carry back the 
Acheulian stage of Palaeolithic time quite to the beginning 
of the Ice age. The many other sections in this valley dis- 
play ice-floated sandstone blocks and deformations of the 
strata attributable to the melting of masses of river ice; but 
these disturbed conditions were absent when human imple- 
ments and the bones of the mammoth, the woolly rhinoceros, 
wild horse, urus, stag, reindeer, lion, and hyaena, were mingled 
in the Menchecourt gravel and sand beds, which are about 20 
to 30 feet above the sea level, under subsequent deposits of 20 
feet of loam and clay, the surface being about 50 feet above 
