VITALITY OF BURIED VEGETABLE GERMS. 255 



era, viz. : Oak, Hickory, Poplar, Maple, Mulberry, Horn- 

 beam, Box -elder, Laurel, Bay, Dogwood, Sumac, Olive, 

 Buckthorn, Magnolia, Smilax, White Cedar, Sequoia, Cy- 

 press, and Sabal. These identifications have been made 

 from scanty and defective material, and we may fairly 

 presume that further investigations will greatly increase 

 the number. Yet these plants, belonging probably to the 

 earliest Cenozoic Epoch, show, according to Lesquereux, 

 "the greatest aifinity with species of our own time." 

 From other beds of the middle or earlier Tertiary we have 

 still other existing genera, such as Persimmon, Beech, 

 Black Gum, Aristolochia, etc. The facts in our possession 

 relative to the middle and later Tertiary Epochs show a 

 most decided approximation to the existing flora. From 

 a pleiocene deposit near Somerville, Tennessee, Lesquereux 

 identified the following recent species, viz. : Carolina Lau- 

 rel, Carolina Plum, Myrtle-leaved Oak, and Common Beech. 

 From the chalky banks of the Mississippi River, near Co- 

 lumbus, Kentucky, a collection was made, of which all the 

 species are recent, viz. : Live Oak, Dwarf Chestnut, Winged 

 Elm, Gmelin's Planer-tree, Entire-leaved Prinos, New Jer- 

 sey Tea, Pecan, Honey Locust, and Sweet Flag. It is true 

 that Dr. D. D. Owen has assigned the deposit containing 

 these remains to the Post-Tertiary Age ; but their position 

 is one hundred and twenty feet below the ferruginous sands 

 containing the bones of the extinct sloth Megalonyx Jeffer- 

 soni; and, as the nature of these species is incompatible 

 with such a climate as we universally associate with the 

 Glacial Epoch, it is quite likely this assemblage of vegeta- 

 ble remains represents the general nature of the arboreal 

 flora in existence near the close of the Tertiary Age.* 



* Dr. Newberry has shown that even the Cretaceous flora of North 

 America was very similar to that now existing. — Amer. Jour. Sci. and 

 Arts [2], xxix., 215 et seq. See also Lesquereux's determinations. — ■ 

 Amer. Jour. Sci. and Arts [2], xlv., p. 104, and xlvii., p. 286. 



