578 



CEXOZOIC ERA— AGE OF MAMMALS. 



skeletons of the large Pachyderms are usually more perfect. In the 

 Kirkdale Cave, England, the teeth and other parts of 300 individuals of 

 the Cave-hyena were found. In the Gailenreuth Cave, Franconia, the 

 remains of 800 Cave-bears were obtained. In a Polish cave Romer 

 recently found the remains of at least 1,000 Cave-bears,* and from one 

 in Sicily, twenty tons of hippopotamus-bones have been taken, f In 



Fig. 946.— Skull of Hyena spelaea, x |. 



many bone-caves are found also the bones and rude implements of 

 primeval man. Of these we will speak more fully hereafter. 



Origin of Cave Bone-Rubbish. — When it was supposed that the Drift 

 was caused by a great wave of translation sweeping across the conti- 

 nent and carrying ruin in its course, the phenomena of bone-caves were 

 supposed to give countenance to this view. Animals of all sizes and 

 kinds were supposed to have huddled together in these caves, forget- 

 ting their mutual hostility in the sense of a common danger, and per- 

 ished miserably together there. 



But at present it is usually believed : 1. That these caves were the 

 dens of the larger Carnivores, especially the Cave-bear and Cave-hyena, 

 which dragged their prey there to devour them, and also later the 

 abodes of men ; 2. That also the floating bodies of large Herbivores, 

 such as the Elephant, Rhinoceros, etc., were carried into them by the 

 flooded rivers which then ran at that level ; and 3. That during the 

 Champlain epoch, when water ran through these caves in large quanti- 

 ties, bones and earth were drifted in from above, through fissures and 

 subterranean passages, and thus found their lodgment in the caves. 

 This last was probably the principal source of the bone-rubbish in 

 most cases. 



Origin of Bone-Caverns. — In limestone regions caverns are very 

 abundant everywhere. They do not seem to be enlarging now ; but 

 on the contrary to be in most cases filling up either with rubbish or 

 with stalactitic and stalagmitic deposit. In some cases streams still run 



Science, vol. iii, p. 490, 1884. 



+ Prestwich, Geology, vol. ii, p. 508. 



