55 



upon shoAAed unpleasant effects from tlie mere handling of this species in 

 collection and determination. Six others were poisoned as a result of the 

 rubbing process, only five escaping entirely. In almost every class I have 

 numerous cases of poisoning easily referable to this form. The poisonous 

 property seems most active during the flowering season, the plant being 

 practically innocuous after seed maturation. The effect shows first as a 

 hyperfemia, later becoming vesicular and even pustular if untreated. It 

 yields readily, however, to ordinary emollient treatment and can be fairly 

 limited in its spread by frequently bathing the adjacent parts with alcohol. 

 My attention was first caUed to the poisonous character of the plant by 

 Dr. D. T. MacDougal and continued observation but serves to confirm the 

 view that many cases of poisoning attributed to the poison ivy should be 

 referred to this species. The attractiveness of the fiower serves to lead 

 many persons to collect it in large masses and if the results reported 

 above are at all indicative, it is doubtless chargeable with many cases of 

 poisoning occurring in the early spring. 



The nettles including Urtica dioica L., Urtica gracilis Ait. and Urtica- 

 strum divaricatum (L.) Kuntze, poison through the action of acrid con- 

 stituents, producing an intolerable burning. The inflammation, however, 

 yields so readily to treatment by cooling lotions and is so ephemeral in its 

 character if untreated, that the plants are to be considered as annoying 

 rather than poisonous. None of twenty-two subjects escaped the intense 

 burning following the handling of these forms. The inflamed condition 

 never persisted over two or three hours even after a rather vigoi'ous 

 whipping of the skin with the plants. 



Of the Smartweeds, two. Polygonum hydropiper L., and P. punctatum 

 Ell., it is said ''cause itching and burning of the skin." In the experi- 

 ments tried this proved true if the expressed juice was applied to mucous 

 membranes, especially those of the eye. In no case was any irritation 

 observable where the application was to the skin. In this case also, the 

 irritation was but temporary and yielded readily to bathing the affected 

 parts in cold Avater. 



That Pokeberrj- (Phytolacca decandra L.) contains a principle which 

 is an internal poison is M'ell known. The claim, however, that the "green 

 plant and root irritate the skin, affecting chiefly mucous membranes," 

 does not seem to be so well made out. Only eight subjects were treated 

 with this species and in no instance were any inflammatory symptoms ob- 



