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MANUAL OF POISONOUS PLANTS 



Fig. 343. Poison Sumac ^Khus Vernix), show- 

 ing leaves, fruit and leaf-scars, one-fourth natural 

 size. (Chesnut, U. S. Dept. Agr.) 



a sensation of irritation about the eyes and throat from the specimens of 

 poison oak collected on the first named date, while working with the plants 

 under an Argand gas burner, but nothing further was noticed. No unpleasant 

 symptoms were observed from the poison oak {R. venenata=R. Vernix) col- 

 lected Oct. 6th. From that collected Oct. 10, he experienced symptoms similar 

 to those observed Sept. 28th. On Oct. 12th a single vesicle with a peculiar 

 thick cover appeared; the next day another and larger appeared on the wrist; 

 two others came on the fourth day; others continued to appear up to Nov. 

 3rd, after which data the effervescences gradually subsided and were no longer 

 ;perceptible. In another case described by Dr. White, the head was greatly 

 ;swollen and features greatly disturbed. The skin of the face and neck was 

 deeply oedematous and largely covered with vesicles of all sizes "many of which 

 were seated on an erythematous base, others being still in their papular stage 



