Geological Age of Man. 27 



man, less vague than that which we can at present assign to 

 the event. But so far as our interpretation of physical move- 

 ments has yet gone, we have every reason to infer that the 

 human race is extremely modern, even when compared to 

 the larger number of species now our contemporaries on the 

 earth. 



In fluviatile deposits, such as the loess of the Rhine and 

 the Mississippi, where the land and freshwater shells are 

 of living species, we find no human bones or articles fabricat- 

 ed by man ; nor in the elevated tufaceous strata near Naples, 

 or the raised beaches of Norway, or the brackish-water strata 

 several hundred feet high, bounding the Baltic, nor in the 

 stratified glacial drift, in all of which marine shells are im- 

 bedded, referable, with few exceptions, to living species. I 

 have explained my reasons for not assenting to the alleged 

 antiquity of certain human bones, supposed to have been as 

 ancient as the Mastodon and Megalonyx, in the loess near 

 Natchez on the Mississippi.* In cave deposits which con- 

 tain the bones of extinct quadrupeds, mixed with the re- 

 mains of a small number of recent species of the same class, 

 no human skeletons or fabricated articles have been found. 

 There are, indeed, some few alleged exceptions to this rule, 

 •but by no means sufficiently authenticated to prove that 

 man co-existed with an extinct mammiferous fauna ; for the 

 possibility of human remains having become subsequently 

 mingled with those of older date, whether by natural causes 

 or by burial in the stalagmite and alluvium of caverns, must 

 be taken into account. In South America no less than 800 

 caves were explored by those indefatigable naturalists, Lund 

 and Clausen, and they obtained the bones of 101 species of 

 mammalia belonging to 50 genera, a fauna more rich and 

 varied than that now inhabiting the same country. Among 

 all these, only one species of quadruped could be identified 

 with the recent. After ransacking so many hundred caves 

 they met with human bones in six only, and in one of these 

 alone were they mixed with the remains of extinct animals 

 in such a manner as to seem to imply that they had belonged 

 to the same epoch. In this one example, the bones are said 



* See my Second Visit to the United States, vol. ii., p. 196. 



