THE TUNDRAS AND STEPPES OF PREHISTORIC EUROPE. 327 



of bedding may be seen, and the beds have yielded fresh- water shells. 

 This, however, is exceptional. Loss is, for the most part, a subaerial 

 accumulation — a wind-blown deposit. This is shown not only by the 

 rounded character of its minute constituents and by the general absence 

 of bedded arrangement, but by the abundant presence of snail shells 

 and the frequent occurrence of relics of land animals. Its organic 

 remains are essentially terrestrial. Moreover, its particular distribu- 

 tion — the mode in which it occurs — points clearly to the action of prev- 

 alent winds. Thus, although it is widely developed over low-lying 

 regions, it nevertheless sweeps up to heights of 200 to 300 feet and 

 more above the bottom of the great river valleys. Not only so, but 

 ever and anon it extends across the hills and plateaus between adjacent 

 valleys, wrapping the whole land, in short, like a mantle. Again, in 

 many places, we find it heaped up in the lee of hills, the exposed wind- 

 ward slopes of which bear no trace of it, while in certain valleys it 

 shows a similar partial distribution. 



Among the organic remains yielded by the loss are some that indi- 

 cate arctic conditions, while others are strongly suggestive of a steppe 

 climate, and yet others tell us of forest lands. It is impossible that all 

 the creatures referred to could have lived side by side in the same 

 region, and annual migrations will not wholly explain their appearance 

 in the same deposit. The evidence leads to the conclusion that the 

 accumulation of the loss must represent a long period of time daring 

 which climatic changes took place. Fortunately now and again the 

 lossic accumulations exhibit a succession of faunal zones — different 

 suites of organic remains occurring at different levels. And a similar 

 and corresponding succession has been discovered in many of the caves 

 of middle Europe. 



A tundra fauna is the earliest of which we have any record in the 

 loss and in the particular caves referred to, and it is worth while to 

 glance for a moment at the former wide distribution of that fauna in 

 Europe. It will be remembered that two of the most characteristic 

 tundra forms are the banded and the Obi lemmings. Now, remains of 

 both these species have been met with again and again over all central 

 Europe — in Russia, Poland, Austria-Hungary, north and south Ger- 

 many, north Switzerland, France, Belgium, and England. Sometimes 

 they occur in single specimens, at other times they are extremely 

 numerous, the remains of several hundreds having been obtained at 

 various localities. In many places both species of lemming are found 

 together; elsewhere either one or other occurs alone. The banded 

 lemming, as a rule, has left its remains most abundantly in hilly and 

 upland tracts, while those of the Obi lemming are met with more fre- 

 quently in low-lying areas — a distribution quite in keeping with that 

 which obtains at present in the tundras. That these arctic animals 

 were not mere passing or occasional visitors is shown by the fact that 

 young and full-grown individuals occur together in hundreds at various 



