232 DARWINIANA. 



Asia, as well as of Atlantic North America, but all 

 wanting in California ; one Juglans like the walnut 

 of the Old World, and another like our black walnut ; 

 two or three grapevines, one near our Southern fox 

 grape or muscadine, another near our Northern frost- 

 grape ; a Tilia, very like our basswood of the Atlan- 

 tic States only ; a Liquidambar ; a magnolia, which 

 recalls our M. grandiflora ; a Liriodendron, sole repre- 

 sentative of our tulip-tree ; and a sassafras, very like 

 the living tree. 



Most of these, it will be noticed, have their near- 

 est or their only living representatives in the Atlantic 

 States, and when elsewhere, mainly in Eastern Asia. 

 Several of them, or of species like them, have been 

 detected in our tertiary deposits, west of the Missis- 

 sippi, by Newberry and Lesquereux. Herbaceous 

 plants, as it happens, are rarely preserved in a fossil 

 state, else they would probably supply additional tes- 

 timony to the antiquity of our existing vegetation, its 

 wide diffusion over the northern and now frigid zone, 

 and its enforced migration under changes of climate. 1 



Concluding, then, as we must, that our existing 

 vegetation is a continuation of that of the tertiary 



1 There is, at least, one instance so opportune to the present argu- 

 ment that it should not pass unnoticed, although I had overlooked the 

 record until now. Onoclea sensibilis is a fern peculiar to the Atlantic 

 United States (where it is common and wide-spread) and to Japan. 

 Prof. Newberry identified it several years ago in a collection, obtained 

 by Dr. Hayden, of miocene fossil plants of Dakota Territory, which is 

 far beyond it present habitat. He moreover regards it as probably 

 identical with a fossil specimen " described by the late Prof. E. Forbes, 

 under the name of Filiates Hcbridicus, and obtained by the Duke of 

 Argyll from the island of Mull." 



