PREFACE. 



In the following general notes on the flora of the Yellowstone 

 National Park but little has been attempted beyond an enumer- 

 ation of the Flowering Plants (Phsenogamia) and Vascular 

 Cryptogams (Pteridophyta). 



The list of plants has been compiled from the following 

 sources, neglecting a few species in the older collections, of 

 doubtful synonym}'^ : — 



A collection of 605 species made by the author in the Yellowstone National 

 Park during August and Septembei-, 1884, and June, July, August 

 and September, 1885. 



A collection made by Robert Adams, .Jr., in 1871. 



In U. S. Geol. Surv. Montana and adjacent Terr. F. V. Hayden. 

 Wash., 1872. 



By Prof. John M. Coulter in 1872. 



In U. S. Geol. Surv. Montana, Idaho, Wyoming and Utah. 

 F. V. Hayden. Wash., 1873. 



By Dr. C. C. Parry in 1873. 



In Reconnaissance of Northwestern Wyoming. Capt. W. A. Jones. 

 Wash., 1874. 



By Dr. W. H. Forwood in 1881. 



In Report of Lieut. Gen. P. H. Sheridan of liis Expedition through 

 the Big Horn Mts., Yellowstone Park, etc. Wash., 1883. 



By Dr. W. H. Forwood, in 1882. 



In Report of an Exploration of parts of Wyoming, Idaho and 

 Montana, made by Lieut. Gen. P. H. Sheridan. Wash., 1882. 



The thanks of the author are due to Dr. Asa Gray, Sereno 

 Watson, Wm. M. Canby, Prof. C. S. Sargent, Dr. Geo. Yasey, 

 F. L. Scribner, M. S. Bebb, and Wm. Boott, for the determina- 

 tion of nearly all the species of his collection. 



FRANK TWEEDY. 

 Washington, D. C, Ajml 4, ISSG. 



