MIOCENE FLORA. 



The plants of this formation described from Alaska by Professor Heer ; 

 from the Fort Union Group by Dr. Newberry ; from Carbon and Washakie, 

 Wyoming, by myself, and those which I have to describe now from the 

 Mauvaises Terres of Nevada and from divers localities of California and 

 Oregon, are all referable to the Miocene. They may represent, however, 

 peculiar geological or geographical divisions which it may be interesting 

 to consider separately. The distinction is not yet clear ; but these local 

 floras may serve to fix hereafter different stages of the American Miocene. 



Indeed, for the present, fossil plants have been obtained from a large 

 number of localities of the Miocene ; but though taken altogether they 

 constitute an important representation of the flora, the number of speci- 

 mens of each locality does not afi"ord sufflcient data to authorize any 

 reliable conclusion in regard to their relative stage in either. What . 

 has been done for the flora of the Oligocene must be continued for that 

 of the Miocene. I have described separately the plants obtained from each 

 group or peculiar locality from which a number of specimens have been 

 examined and determined either by myself or by other authors, and putting 

 in juxtaposition all these materials in a table of distribution, it will be 

 possible, perhaps, to see some distinct relationship between a few of the 

 localities ; or at least there will be for the future some points of comparison 

 for relating the newly discovered plants. 



The first group of Miocene plants described here is that of the Bad Lands 

 of Dakota. Fine materials have been sent to me for examination, first by 

 Professor Wm. Denton, later by Professor McBride, and recently by Pro- 

 fessor N. H. Winchell. All the species of this group are described below 

 and figured in pi. xlvi to pi. xlix. 



The plants of a second group, that of Fort Union, have been described 

 by Dr. Newberry in his memoir on the " Later Extinct Floras of North 

 America" (Lyceum of Nat. Hist, of New York, vol. ix, April, 1868), and 

 figured as a separate volume of " Illustrations of the U. S. Geol. Survey 



219 



