OP THE CAVES OF CRESWELL CRAGS. 607 



in the contents of any other cavern, which may be explained by 

 these being nearer the surface of the ground above, and therefore 

 more exposed to the attack of the acid-laden water than the great 

 majority of caverns. 



It may be added that the same results may be produced by 

 chemical action intensified by pressure, as pointed out by Mr. Sorby's 

 experiments. 



V. General Conclusions as to Pleistocene Fauna oe Creswell 



Caves. 



It remains now to sum up the results of these explorations of the 

 Creswell Caves. The associated species of the Robin-Hood Cave are 

 the same as those of the Church Hole ; and there can be no doubt 

 that the caves were inhabited at the same time. The fauna of the 

 Red Sand and of the Cave-earth is alike in both. The palaeolithic 

 hunter who first appeared used ruder implements than those who 

 succeeded him. 



The animals belong to groups which spread over Central Europe, 

 from the Pyrenees as far north as the Elbe, and swung to and fro 

 according to the season. They would naturally find their way from 

 the low grazing-lands now occupied by the German Ocean up the 

 line of the Trent to Creswell, as may be seen by the accompanying 

 map (fig. 9). 



In the absence of physical evidence it is useless to speculate on 

 their relation in this district to the Glacial period, because they 

 lived in Europe in Preglacial, Glacial ( = Interglacial), and Post- 

 glacial times. 



A. iVo Cave-fauna proved to be Pre- or Interglacial. 



Nor, may it be added, is there satisfactory evidence offered by 

 any cave in this country which enables us to fix the relation to the 

 Glacial age of any cave-fauna in particular. In the Victoria Cave, 

 for example, quoted by Mr. Tiddeman, Mr. James Geikie, and others, 

 as decisive of the Pre- or Interglacial age of the cave-fauna below 

 the clay, the whole question turns on the age of the clay above the 

 bone-bearing strata at and within the entrance. And this is not 

 proved to be " boulder-clay " (' Ice Age,' p. 510), because there are 

 no boulders in it ; nor is it proved to be Glacial (' Nature,' 1876, 

 p. 505), because clay of that kind is now being deposited in that 

 very cave. That it has ultimately been derived from the wreck of 

 the Boulder-clay at a higher level, which was formerly spread over 

 the country, and has been washed in by the rains, is very probable. 

 Nor do the piles of travelled blocks which occur in the talus out- 

 side the entrance throw any light on the point, because they are 

 rernanies and not in situ. They may have tumbled from the cliffs 

 above during the accumulation of the talus, and long after the 

 glaciers had retired from Yorkshire. These doubts as to the pre- 

 or interglacial age of the fauna below the clay which grew up in my 

 mind while intrusted with the conduct of the exploration, and have 



