IMPORTANT POISONOUS PLANTS 125 



Hypericum perforatum L. Common St. John's- Wort. 



Naturalized in Eastern U. S. A well known vesicant. 



Hypericum Ascyron L. Great St. John's-Wort. 



Most widely distributed species in the state, in woods or borders of woods. 



Violaceae. 



Viola odorata L. Sweet Violet. 



Commonly cultivated in greenhouses. Said to be somewhat poisonous. 

 Underground parts of the plant are emetic. 



Viola cucullata Ait. Common Blue Violet. 



The most widely distributed species in the eastern states ; the roots, like the 

 preceding, are emetic. 



Loasaceae. 



Mentzelia ornata Torr. & Gray. Mentzelia. 



The backwardly-barbed trichomes sometimes produce mechanical injuries. 

 Found in Northwestern Iowa on the Big Sioux near Sioux City, and west and 

 southwest. 



Datiscaceae. 



Datisca glomerata (Presl) Benth & Hook. 



California fish poison. 



Cactaceae. 



Opuntia Rafinesquii Engelm. Cactus. 



Found in sandy soil in the state. The barbed trichomes cause mechanical 

 injuries. 



Other spiny species of Opuntia, Mammillaria and Cereus, largely developed 

 in southwestern United States, produce similar mechanical injuries. 



Anhalonium Lewinii Henn. Mescal Bean. 



This cactus contains a narcotic substance which has long been used by the 

 Indians of Mexico and adjacent regions to produce narcosis. 



Cereus grandiflorus Mill. Night-blooming Cereus. 



It has been regarded with suspicion where the plant is cultivated and native. 

 Frequently cultivated in the United States. 



Thymelaeaceae. Mezereum Family. 



Daphne Mezereum L. Spurge Laurel. 



This is a well-known poisonous plant of Europe and is occasionally culti- 

 vated. It contains the glucosides daphnin and daphnetin. 



Other cultivated species in North America are known to be poisonous and 

 several of the related genera native to Asia and Australia are poisonous. 



Dirca palustris L. Leather-Wood, Moose-Wood. 



Found in the North to Iowa. The bark is acrid, the berries narcotic and 

 poisonous. 



Elaeagnaceae. Oleaster Family. 



Hippophae rhamnoides Linn. 



A native of Europe but cultivated in the United States and said to be 

 narcotic. 



Araliaceae. Ginseng Family. 

 Fatsia horrida (Smith) B. & H. 



From Isle Royal, Lake Superior region, to the Rocky Mountains and Alaska, 

 and California. It causes mechanical injuries. 



