30 /. iter Extinct Floras of North America. 



'brdii, (Lesqx.), Andromeda ditbia, (Lesqx.), Andromeda 

 'inifolia^ Eleagnus inequalis (Lesqx.), extinct; from Mis- 

 sissippi Rhamnus marginatus, (Lesqx.), Quercus Sqffbrdii, 

 I. and Magnolia Hilgardiana, (Lesqx.). 



From Bome Tertiary beds in New Jersey, supposed by Prof. 

 •k to be Pliocene, I have received a small collection of 

 plants, which include a three-lobed Liquidanibar, a Cercis and 

 one or two species of oak. 



By far the largesl representation of our Tertiary flora is. how- 

 ever, contained in the collections made by J)r. ECaydeu on the 

 upper Missouri, of which the greater number of species are 

 described in the present memoir. These plants are from the 

 lignites proved by the associated fossils to be of Miocene age. 

 They were collected at various points on the Missouri River,al 

 Fort Clarke, at Red Spring, thirteen miles above, at Fort 

 Berthold at ('row Hills, one hundred miles below Fori Onion, 

 at the month of the Yellow-tone, on < )'Fallon's Creek one hun- 

 dred miles above the mouth of the Yellowstone, and in the 

 Valley of that stream. 



- •me of the species are common to several of these localities. 

 and their can be no doubt oi the parallelism of the beds which 

 contain them. The molluscous fossils which accompany them 

 have been carefully studied by Mr. Meek, and are considered 



him indicative of Miocene age. The list of the sp< 

 obtained from this horizon by Dr. Hayden is as follows: 



