98 



Although it is not clearly demonstrated how the species 

 arrived in this country, nor how most of the stations have 

 originated, it is obvious that already the plant has thoroughly 

 established itself, not only on the borders of cultivated fields 

 and areas adjacent thereto, but along roadsides, in uncultivated 

 lands, and waste places.* The long horizontal roots, perennial 

 and often deep seated, suggest the possibility that in this plant 

 we may well find a rival to the Canada Thistle in persistence. 

 Academy of Natural Sciences of Philadelphia. 



ADDITIONS TO THE FLORA OF WESTERN 

 OREGON DURING 1921. 



By James C. Nelson 



A few more species remain to be added to the flora of the 

 Willamette Valley as the result of the past season's collecting. 

 Our list of local species appears to approach completion very 

 much as certain geometric curves approacii a straight line — 

 always coming nearer, but never reaching absolute contact 

 this side of infinity. Let it be again remarked, as in previous 

 lists, that all of these species were growing without cultivation, 

 and seem in all cases to be permanent members of our flora. 



The total number of Oregon species that have been re- 

 ported as not mentioned in Piper and Beattie's Flora of the 

 Northwest Coast has now reached 371. Adding these to the 

 161 7 species of that manual, we are now within 12 species of the 

 2000 predicted earlier in this series. Another season should 

 complete this total. 



Introduced species are marked*. 



1. Equiseticm hyemale L. var. calif ornicum Milde. Not in- 

 frequent along streams in sandy woods. Determined by W. 

 R. Maxon. 



2. Equisetum paliistre L. Very common in the low ground 

 north of Chemawa, Marion Co., but rarely fruiting. This was 



* The recent report by O. A. Stevens in (he Bulletin of the Toriey Botanical 

 Club for April 1922 of its frequence in tlie Red River Valley of North Dakota, 

 Minnesota, and adjoining Canada is indicative of its already wide dispersal 

 in yNnierica. 



