REPORT ON THB GBOI-OGY OF NORTH AMERICA. 23 



occupy the highest elevations above the secondary and tertiary 

 classes, and consequently could not have been formed by our 

 existing rivers. It is entirely unmixed with the tertiary, and 

 destitute of the fossils vv^hich characterize the latter; it must 

 therefore be considered as distinct from it, at the same time 

 that it is unlike the modern alluvial, whose origin is clearly at- 

 tributable to the overflow and inundation of our rivers." 



This red earth is precisely similar to the mixture of sand and 

 clay which we may witness discharged from some of the turbid 

 rivers of the Mississippi in the present day. It is seen covering 

 tertiaries at Augusta in Georgia, Columbia in South Carolina, &c. 

 The ancient alluvial beds, resembling in all respects tliose at 

 Bordentown, are seen along the Santee canal in Georgia, whei'e 

 they repose on secondary beds. In excavating this canal, not 

 only the dark vegetable clay before described, but much lignite 

 and the remains of a Mastodon were found, marking the agree- 

 ment of the deposit in all respects with the corresponding beds 

 at Baltimore and elsewhere. 



Fossil Mammalia of the United States. — ^The extinct species 

 of the higher orders of animals found fossil in the United States 

 are Mastodon giganteum, Elephas primigenius, another Ele- 

 phant (a tooth only being known, differing considerably from 

 the tooth of either the living or fossil species). Megatherium^ 

 Megalonyx, Bos bombifrons, Bos Pallasii, Bos latifrons, 

 Cervtis americanus, or fossil Elk of Wistar, and Walrus. 



Of living species also found fossil, we may enumerate the 

 Horse, the Buffalo, and three or four species of Deer. The 

 situations in which these have been found have been either very 

 recent undisturbed alluvial bogs, or a slightly disturbed marshy 

 deposit like Big Bone Lick, neither of them covered by the 

 general diluvium; thirdly, boggy beds containing lignite re- 

 ferrible to an ancient alluvium, covered by diluvial sand and 

 gravel ; and lastly, the floors of caves, buried to a very small 

 depth with earth not described. 



The largest collections of bone remains occur in boggy grounds 

 called Licks, affording salt, in quest of which the herbivorous 

 animals, wild and domestic, enter the marshy spot and are 

 sometimes mired. The most noted of these deposits is Big 

 Bone Lick in Kentucky, occupying the bottom of a boggy val- 

 ley kept wet by a number of salt springs, which rise over a sur- 

 face of several acres. The spot is thus described by Mr. Cooper : 

 **The substratum of the country is a fossiliferous limestone. At 

 the Lick the valley is filled up to the depth of not less than thirty 

 feet with unconsolidated beds of earth of various kinds. The 

 uppermost of these is a light yellow clay, M'hich apparently is 



