172 PROCEEDINGS OF THE AMERICAN ACADEMY 



He remarked that, for obvious reasons, the remains of 

 plants are not so likely to be found in recent terrestrial 

 formations, as the bones of animals ; but when they do 

 occur, they furnish most important data. Researches into 

 vetretable fossils of the tertiary and quaternary formations 

 have recently been commenced in this country by Mr. Leo 

 Lesquereux, who has already shown, in the very beginning 

 of these investigations, that some of our species of plants 

 were in existence anterior to the drift or glacial epoch, and 

 even in the later tertiary period. For instance, in the chalky 

 banks of the Mississippi River, near Columbus, Kentucky, 

 regarded by Mr. Lesquereux as anterior to the drift, this 

 accurate botanist had identified fossilized leaves of our Live- 

 Oak, Honey-Locust, Pecan, Planer-tree, Chinquapin Chest- 

 nut, and Prinos lucidus, besides those of an Elm and of a 

 Ceanothus, which were only doubtfully referable to existing 

 species. The position of the strata bearing these fossil leaves 

 had been indicated by Professor J). J). Owen " as about one 

 hundred and twenty feet lower than the ferrugineous sand in 

 which the bones *of the Megalomjx Jeffersonii were found " ; 

 so that if not anterior, they must have been immediately sub- 

 sequent to the glacial period; — most likely the latter, since 

 all the vegetable remains of this deposit, which were in a 

 determinable condition, were either positively or probably 

 referred to existing species of the North American flora, 

 although most of them now inhabited a region a few de- 

 grees farther south. Again, in a deposit, certainly older than 

 the drift, near Somerville, Tennessee, which Mr. Lesque- 

 reux regarded as belonging to the lower or middle pliocene, 

 among fossil leaves all apparently referable to genera of the 

 present flora, two fifths of the species were identified by Mr. 

 Lesquereux with existing species ; those of which the iden- 

 tification was undoubted, viz. Per sea Carolinensis, Prunus 

 CaroUniana^ and Quercus myrtifolia, now belonging to the 

 warm sea-coast and islands of the Southern States. 



Professor Gray remarked that this coincided with other 



