146 ABSENCE OP HU3IAN BONES EXPLAINED. chap. viii. 



to have coexisted in France with the mammoth. The same 

 theory which will explain the comparative rarity of such 

 species would no doubt account for the still greater scarcity 

 of human bones, as well as for our general ignorance of the 

 post-pliocene terrestrial fauna, with the exception of that 

 part of it which is revealed to us by cavern researches. 



In valley drift we meet commonly with the bones of quadru- 

 peds which graze on plains bordering rivers. Carnivorous 

 beasts, attracted to the same ground in search of their prey, 

 sometimes leave their remains in the same deposits, but more 

 rarely. The whole assemblage of fossil quadrupeds at present 

 obtained from the alluvium of Picardy is obviously a mere 

 fraction of the entire fauna which flourished contemporane- 

 ously with the primitive peojile by whom the flint hatchets 

 were made. 



Instead of its being part of the plan of nature to store up 

 enduring records of a large number of the individual plants 

 and animals which have lived on the surface, it seems to be 

 her chief care to jDrovide the means of disencumbering the 

 habitable areas lying above and below the water of those my- 

 riads of solid skeletons of animals, and those massive trunks 

 of trees, which would otherwise soon choke up every river and 

 fill every valley. To prevent this inconvenience she employs 

 the heat and moisture of the sun and atmosphere, the dissolv- 

 ing power of carbonic and other acids, the grinding teeth and 

 gastric juices of quadrupeds, birds, reptiles, and fish, and the 

 agency of many of the invertebrata. We are all familiar with 

 the efficacy of these and other causes on the land; and as to the 

 bottoms of seas, we have only to read the published reports of 

 Mr. MacAndrew, the late Edward Forbes, and other experi- 

 enced dredgers, who, while they failed utterly in drawing 

 up from the deep a single human bone, declared that they 

 scarcely ever met with a work of art, even after counting tens 

 of thousands of shells and zoophytes, collected on a coast-line 



