520 SCIENCE PROGRESS 



unknown, at all events south of Piedmont, but the fauna of 

 E. antiquus, on the other hand, is both richly represented 

 and very persistent, surviving into the Mousterian stage. 



In the northern countries where both faunas occur it has 

 been suggested that their intermixture may be due to remain- 

 ment, i.e. to the destruction of an earlier deposit and its re- 

 distribution, along with its contained fossils, in a later 

 deposit. Prof. Boyd Dawkins has attributed it to seasonal 

 migrations. 



The Acheulean Stage 



The Acheulean industry is the direct descendant of the 

 Chellean, and the boucher is still the characteristic implement, 

 but it is a different boucher, distinguished by its finer workman- 

 ship and more elegant form. It is much flatter, not so thick, 

 and consequently lighter ; the flaking is not so coarse, and the 

 edge has been worked by repeated minute retouches into an 

 even, regular line, very different from the jagged edge of the 

 Chellean form. It was thus rendered more trenchant, so that 

 the Acheulean boucher is not only a better finished but a 

 more efficient implement. 



The same kind of refinement is seen in the scrapers and 

 chisels, and it leads on to the Mousterian point, to be described 

 presently, which makes its first appearance in the Acheulean 

 stage anticipatory to its abundant development later on. 



The Acheulean fauna, even in France, is a mixed fauna ; 

 it includes both the southern forms characterised by Elephas 

 antiquus, and the northern, equally characterised by the 

 mammoth. 



The mammoth, though not so large as its predecessor 

 E. antiquus, was larger than either of the existing species of 

 elephant, and attained a height of over 16 ft. Its tusks, large 

 and strongly recurved, were sometimes as much as 23 ft. in 

 length. Its warm coat of close fur and long hair no doubt 

 served in the first place as a protection against the rigours 

 of a cold climate : a further protection was afforded by a layer 

 of fat 8 cm. in thickness beneath the skin. Its teeth, by 

 which it is generally recognised in the fossil state, differ from 

 those of E. antiquus by their greater breadth and more numer- 

 ous transverse lamellae ; the lamellae themselves are narrower 

 and crowded closer together; the enamel on their surface is 



