786 GEOLOGY OF TQE YELLOWSTONE NATIONAL PARK. 



The flora of the older or acid series will be first considered. Of the 

 79 species, 42 are either new to science or not specifically named, leaving 

 37 species having a distribution beyond tlic limits of the Park. Following 

 is a list of these species: 



Aspleuium erosiim (Lx.)- Uliiius rb am iii folia Ward. 



Lygodium kault'usii (Heer). Ficus uugeri Lx. 



Taxites olriki Ileer. * Ficus asimiiia'tblia Lx. 



Sequoia couttsiie Heer. Laurus primigeiiia ! Uiig. 



Sequoia laiigsdorfii (Bigt.) Ileer. Laurus princeps Lx. 



Spargauium stygium Heer. Laurus calif'ornifa Lx. 



Cyperacites angustior Al. Br. Laurus grandis Lx. 



Musopliylhnn coiiiplieatuin Lx. Ciuiiamoniniii spectabilis Heer. 



Juglaus rugosa Lx. Platanus guillehiKe Gcipp. 



Juglans schimperi Lx. Legumiuosites cassioides Lx. 



Myrica scottii Lx. Sapindus attiiiis Lx. 



Populus glaiidulifera Heer. Sapindus aLatus Ward. 



Populus speciosa Ward. Sapindus grandifolius Ward. 



I'opulus dapbnogenoides Ward. Paliurus coloinbi Heer. 



Salix Lavateri Heer. Zizyplius serrulatus Ward. 



Fagus antipofli Heer. Tilia i)opuliiolia Lx. 



Quercus consimilis Xewby. Aralia notata Lx. 



Quercus olafseni Heer. Cornus uewberryi Hollick. 



These 37 species have the following distribution: Five are found in the 

 coal-bearing Laramie, 5 in the Denvei- and Livingston, 17, or nearly 50 per 

 cent, in the Fort Union, 9 in the Green River group, and 11 in the Aurifer- 

 ous gravels of California. Of the species common to the acid rocks and 

 the Laramie at Denver and Livingston beds, not one is found exclusively in 

 these beds, but tliey are such species as Sequoia Umgsdorfii, Juglans rugosa, 

 Platanus gmUelmcB, and Juglans schimperi, which enjoy a wide geological and 

 geographical distribution. 



The Fort Union element in this flora is a very important one ; in fact, 

 it may be called the dominant element. It includes at least 12 species that 

 have never before been found outsidt- of the type locality. Among these 

 . are Sparganium stggium, Populus speciosa, Populus daphnogenoides, Uhnus 

 ni'niima, Ulmus rliamnifolia, Sapindus affinis, Sapindus grandifoliolus, and 

 Cornus newherrgi. Some of these are represented by as many as 200 indi- 

 viduals, showing that they existed in great abundance, as tliey are also 

 known to have existed at the mouth of the Yellowstone. This abundance 



