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It is said of the Leatherwood (Dirca palustris L.) ttiat tlie "fresli barli 

 applied to the skin causes redness and vesication and sores, which are 

 very difficult to heal." Eight subjects were treated by binding pieces of 

 freshly stripped bark upon their arms, allowing them to remain for 

 periods ranging from two to twenty-four hours. Six showed no evil effects 

 of any kind, while in the cases of the other tAvo a somcAvhat painful hy- 

 peremia resulted, easily reduced by an application of vaseline. Somewhat 

 strangely, the two affected represented the extremes of time, two and 

 twenty-four hours. Three other students chewed the fresh bark for a 

 few minutes and in each case an extremely painful blistering of the 

 mouth resulted. In my own case, tried fubsequently, the mucous mem- 

 branes of the mouth did not become normal for nearly a month. In the 

 ordinary use of the tei-m, the leatherwood is not a contact poison, al- 

 though in exceptional cases it may prove such. 



Aralia spinosa L., Angelica Tree or Hercules Club, Avas found without 

 irritating principle in three cases, the small amount of material available 

 precluding more extended experimentation. It is claimed that "green 

 bark from roots or small shrubs acts as an irritant." As far as the re- 

 sults go the statement is without foundation. 



It is the popular belief that Solanum Dulcamara L., poison or purple- 

 leaved nightshade is one of the most virulent contact poisons. By some 

 authorities it is claimed to be an even more virulent skin poison than 

 poison ivy, the symptoms being similar, but the poison much more diffi- 

 cult to eradicate from the system. Tests made upon fifteen subjects failed 

 utterly to justify the popular view. The plants were used in all stages 

 and at all seasons, but in every case without the slightest irritation. I 

 have tried many times to poison myself with this species, frequently 

 taking plants selected by persons Avho claimed an absolute knowledge of 

 the poisonous character of the form and always without untoward results. 

 The result of these experiments makes it almost certain that the purple- 

 leaved nightshade should not be considered as one of our poisonous plants. 



The "Jimson" weeds (Datura Stramonium L. and D. Tatula L.) also 

 have a bad reputation. Fourteen subjects were tested and in no case was 

 there any sign of inflammation. No experiment Avas made to verify the 

 statement that the forms "occasionally cause a SAvelling of the eyelids." 

 It is probable that none of our native species of Solanaceae are as poison- 

 ous as the foliage of the potato and tomato, to Avhich frequent cases of 

 skin poisoning may be definitely referred. 



