16 TWELFTH ANNUAL REPORT. 



about half as many naturalized and adventive species are known in 

 Minnesota as in the eastern states, the difference being due to the 

 shorter time since the settlement of this state and the proportion- 

 ately less numerous opportunities for them to gain a foot-hold here. 



Preliminary Remarks on the Catalogue. 



Under each species is a statement whether it is abundant, com- 

 mon, frequent, infrequent, or rare, and whether its geographic range 

 extends throughout the state or to limits which are indicated ap- 

 proximately; or, when the observations are insufficient for such 

 statement, the localities where the species has been noted are men- 

 tioned, with the names of the observers. 



The arrangement of families, genera and species strictly follows 

 the fifth edition of Gray's Manual', and wherever a synonym replaces 

 an}'' name that occurs in the Manual, the latter also is given, en- 

 closed by marks of parenthesis.* 



The popular names are mostly such as appear in Gray's Manual 

 and Wood's Class-Book; but in a few instances other names, in 

 general use in this state, and often specially significant, are inserted. 



Introduced species are distinguished from the indigenous, as 

 before mentioned, by being Italicized. 



For the species of our flora that are not described in Gray's 

 Manual, which only included those found east of the Mississippi, 

 descriptions are quoted from other authorities.f The present work 

 thus supplies, with Gray's Manual, the means of identifying all the 

 flowering plauts and ferns known to occur in Minnesota. 



Determinations of numerous difficult species, and notes con- 

 cerning them, have been kindly supplied by Prof. Asa Gray, Mr. 

 Sereno Watson, Mr. William Boott, Dr. George Engelmann, Mr. 

 M. S. Bebb, Rev. T. Morong, and other specialists; and I am in- 

 debted to Dr. George Vasey for the description of the new Aristida 

 basiraraea, Eagelmann, posthumously published. 



*The sources of improved nomenclature have been Watson's Bibliographical Index 

 to North American Botany (Part I; Polypetalai : 1878); Gray's Synoptical Flora of 

 North America (Vol. II, Part I ; 6amopetal?e after Compositte : 1878) ; various papers 

 by Professor Gray in the Proceedinys of the American Academy of Arts and Sciences; 

 Bailey's Catalogue of North American Carices (1884); Vasey's Grasses of the United 

 States (1883); Eaton's Ferns of North America (18S0); and notes in the American 

 Naturalist, the Botanical Gazette, and the Bulletin of the Torrey Botanical Club. 



tCliiefly from Watson's report on the Botany of King's Exploration of the Fortieth 

 Parallel; Porter and Coulter's Synopsis of the Flora of Colorado ; Rothrock's report 

 on the Botany of Wheeler's Surveys west of the One Hundredth Meridian ; Torrey and 

 Gray's Flora of North America; and Gray's Synoptical Flora. 



