PLEISTOCENE CA VE-DEPOSITS. 



99 



were introduced, and gradually accumulated in what is now the 

 upper cave-earth. This upper bed is distinguished from the 

 lower by the marked absence of such animals as hyaena, 

 elephant, rhinoceros, and hippopotamus, and by the presence of 

 certain animals which are confined to it, namely horse and pig. 

 To these species peculiar to the upper cave -earth may prob- 

 ably be added the reindeer, for it seems doubtful whether the 

 remains of that animal said to have been obtained from the 

 lower earth really belonged to that deposit. Eemains of the 

 reindeer, however, certainly occur in the upper bed. From 

 the presence of the pig, and the absence of the more character- 

 istic Pleistocene species that are common in the lower stratum, 

 we seem justified in classing the upper cave-earth as of early 

 Post-pleistocene age. 



The so-called Neolithic layer is separated from the Eomano- 

 Celtic stratum by some thickness of talus, showing probably 

 that the cave had been unoccupied by man for some considerable 

 time before the Eomanised Britons were forced to take refuge 

 there. 



The most interesting point in connection with the deposits 

 of this cave is the evidence which shows that after the dis- 

 appearance of the old Pleistocene fauna of Yorkshire — the 

 hyaenas, elephants, rhinoceroses, and hippopotamuses, with which 

 Palaeolithic man was contemporaneous — there ensued a pro- 

 longed period during which an intensely cold climate supervened, 

 and thick glacier-ice filled the valley of the Eibble. When 

 that ice had melted away, and the land again became fitted to 

 support a mammalian fauna, it was not carnivores such as the 

 hyaena, or pachyderms such as the elephant and hippopotamus, 

 that immigrated thither, but an assemblage of animals more or 

 less characteristic of Post-pleistocene and Neolithic times. The 

 faunas of the two cave-earths could hardly in fact be more 

 strongly contrasted. 



The caves of Belgium, Germany, France, and other countries, 

 have yielded, speaking generally, very much the same kind of 

 evidence as that supplied by the cavern-deposits of England. 



