THE AMERICAN BOTANIST 111 



have been immortalized in the scientific names of plants, rare- 

 ly indeed has any human being so powerfully impressed his 

 contemporaries as to be commemorated in a vernacular plant- 

 name. One occasionally will find a name of this character 

 current over a very limited area : for example, in maijy parts 

 of Polk County, Oregon Hypericum perforatum is known as 

 "Gwin-weed," from the person who is said to have unwit- 

 tingly introduced this pest in nursery-packing ; but such names 

 are merely sporadic and local. All honor to the great pioneer 

 of the Northwest, who deserves to be remembered by a far 

 handsomer and less pestiferous plant than either of the two 

 weeds which now bear his name — /. C. Nelson. [Prof. Nel- 

 son has overlooked the name *'Ransted" often applied to the 

 toad-flax {Linaria vulgaris) in allusion to the person who in- 

 troduced it into the United States. "Jo^"Py^"W^^<i" com- 

 memorates an Indian doctor who used the plant so named in 

 medicine, and "Bowman's-root" is probably similarly derived. 

 The well known "timothy" grass is said to derive its name 

 from Timothy Hanson who introduced it into America about 

 ■1720, though W. Ellis, writing in 1750 calls this St. Timothy's 

 grass. Additions to this list are desired,— Ed.] 



Poison Ivy. — Everybody knows that poison ivy {Rhus 

 toxicodendron) will produce a dermatitis, as the medical 

 wights call it, when applied to the skin of susceptible individ- 

 uals, but the question whether it can produce its well-known 

 ■effects from a distance often comes up without a very satis- 

 factory answer. James B. McNair, after a careful study of 

 all parts of the plant, concludes that contact with the plant 

 is necessary to cause poisoning. In an article published in the 

 American Journal of Botany, he states that neither the 

 anthers, the pollen, the epidermal hairs, the bark, nor the 

 wood is poisonous but that the fresh sap undoubtedly is; in 



