21^] FLORA OF COLUMBIA AND VICINITY 77 



Herbarium, and of the others, except in the case of very rare 

 plants, the gathering of which would mean their extinction, and 

 of some common weeds and escapes whose preservation has 

 been hitherto neglected, dried, but unmounted material exists. 

 All but five or six species have been gathered by the author and 

 have been carefully studied in the field. Three or four sheets, 

 inherited from a former generation, preserve species that have 

 not been recently found. 



The flora has been made to conform as closely as possible, 

 both in nomenclature and in the sequence of orders, families 

 and genera, to Engler and Prantl's Natiirliche Pflanzenfamilien. 

 Synonyms, however, have been freely given, and an attempt has 

 been made to include all names used in Britton and Brown's 

 Illustrated Flora of the Northern States and Canada ; Britton's 

 Manual of the Flora of the Northern States and Canada; 

 Small's Flora of the Southeastern United States; Gray's Man- 

 ual of the Botany of the Northern United States (6th ed.) ; 

 Gray's Synoptical Flora of North America; Beal's Grasses of 

 North America ; and Underwood's Our Native Ferns and their 

 Allies. In the present distracted state of botanical nomenclature 

 it has been thought best to follow Engler and Prantl, at least as 

 to genera, but in the numerous cases of species not given there, 

 the nomenclature of Britton's Manual has been employed where 

 possible. Only in a few instances has this method led to the use 

 of names unfamiliar to American botanists. The most distress- 

 ing example is, perhaps, that of Mespilus for Crataegus. Here 

 two closely related genera have been compressed into one, the 

 haws being united to the medlars. Similarly Camptosorus has 

 been merged into Scolopendrium, and Notholaena into Pellaea. 

 This procedure is the more noticeable in that certain American 

 botanists exhibit a tendency to elevate every sub-genus, or sec- 



