Geological Jge of Boue-Caverns. 121 



race. But if the two be united, an intelligible system is esta- 

 blished — the young Mammoth and Rhinoceros meeting with 

 their parents — Herbivora and Carnivora mixing for the first 

 time perhaps in undreaded society, form a natural series of 

 animals of all habits and sizes. 



All this may appear but a coincidence, unless it can be 

 shown why there should have been this separation in the po- 

 sition of their remains; but the habits of the various animals 

 will yield the explanation. 



Upon the approach of natural death or any catastrophe, the 

 wary and active Carnivora woukl generally retire to, and die 

 in, their dens ; whilst the larger Herbivora would be more 

 likely to leave their bones upon the plains, to be subsequently 

 swept away and entombed by natural operations. But it was 

 not by any sudden or violent action that the great accumula- 

 tion of remains in either position took place. For ages Tigers 

 and Hyaenas did their office, and thousands became their vic- 

 tims. Animals of all sizes were exposed to their attacks ; but 

 the smaller ones, and the younger and weaker individuals of 

 the larger class, were their most common prey ; and it would 

 rarely happen that such died a natural death, or if they did, 

 their bones would seldom fail to become the property of 

 Hyaenas, hence they are almost exclusively found in caverns; 

 but the larger and more formidable Mammoth and Rhinoceros 

 must have less frequently met with violent death ; or when 

 this did occur, their bulk and weight would be against their 

 finding their way into the dens of Hyaenas, and their skele- 

 tons, more or less mutilated, would be left to be swept away 

 and interred in fluviaiile deposits, where they are now so 

 abundantly found. The broken bones to which I have alluded 

 may have had such an origin ; they exhibit no teeth marks, 

 but otherwise, in appearance, would bear out such an idea. 

 Of six bones of Birds found by Dr. Buckland at Kirkdale, 

 the ulna occurred four times, which led him to the ingenious 

 observation that the strong quill-feathers attached to that bone 

 may have prevented it being devoured. It is singular that the 

 same bone should be the only one preserved at Ilford ; espe- 

 cially as a row of strong tubercles proves it to have belonged 

 to some powerful biid of flight, consequently with a strong set 

 of wing-leathers; and if a similar explanation of its preserva- 

 tion be admitted, it affords additional strength to such an in- 

 ference. 



The accumulation in caverns may in reality have occupied 

 more than one geological period ; and long after the last 

 hyaena ceased to exist, have been added to by the Wolf and 

 Fox, to whose operations may be attributed the introduction 



