59 



In the preparation of this note I express appreciation to Prof. 

 S. C. Ball for the donation of his specimens from Cap-des-Rosiers, 

 to the University of Montreal for the loan of twenty-eight speci- 

 mens and to the National Herbarium of Canada for the loan of 

 four specimens. Also, I am grateful to the authorities at the follow- 

 ing institutions for the opportunity to study their collections : 

 Academy of Natural Sciences of Philadelphia, Gray Herbarium of 

 Harvard University, and the New York Botanical Garden. 



Literature Cited 



Barkley, F. A. 1937. A monographic study of Rhus and its immediate allies 



in North and Central America, including the West Indies. Ann. Mo. Bot. 



Gai-d. 24 (3) : 265-498. pi. 10-26. 

 McNair, James B. 1925. The taxonomy of poison ivy, Field Mus. Nat. Hist. 



Publ. 225. Bot. Ser. 4 (3) : 55-70. tab. 1^, pi. 14-24. 

 Britton, N. L., and Brown, A. 1913. Toxicodendron, in Illustrated Flora. 2: 



483-484. 

 Victorin, Marie-. 1935. Rhus Toxicodendron, in Flore Laurentienne. pp. 392- 



393. 



Bailey Hortorium, 

 Cornell University, 

 Ithaca, N. Y. 



Useful Source Book. Every teacher and worker in science is 

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 has a dozen other applications in the arts. Even henna (the flower 

 of Paradise) dyes feathers as well as human hair. Pine oil has 

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 one considers it may be a perfume base or a metal cleaner. 



