580 ♦ REPORT OF STATE GEOLOGIST. 



It is wise for persons with sensitive skins, or who are at all suscep- 

 tible to plant poisoning, to avoid handling any of the sumachs. Cases 

 are known, and are, indeed, not uncommon, where severe poisoning- 

 has resulted from handling the crimson fruit masses of the ordinary 

 sumach, which is classed as not poisonous. In the cases of this kind 

 seen, the poisoning seemed to originate in the mucous membrane of 

 the lips and thence to spread rapidly over the face. 



The forms just mentioned are by far the worst of our plants of this 

 type. The following plants are harmless to many people, but are 

 recognized skin irritants, and should be avoided by those liable to 

 plant poisoning. 



All of the spurges (Euphorbias) are extremely acrid, so much so, 

 indeed, that they are classed among poisonous plants by many authori- 

 ties. Loudon says, "Every one is so acrid as to corrode and ulcerate 

 the body wherever applied." The most dangerous form locally is 

 Euphorbia corollata, easily recognized by its erect habit and the white 

 petal-like appendages of the involucre. It is largely gathered for 

 decoration and is probably responsible for some cases of poisoning 

 otherwise referred. 



Indian Tobacco (Lobelia inflata) when applied to the skin produces 

 in many cases a serious and persistent irritation. 



The Yellow Lady's Slipper (Cypripedium hirsutum) at certain 

 stages, especially about the flowering season, is very irritating to the 

 skin, in some cases producing as serious results as "ivy poisoning." 

 Probably many cases of poisoning attributed to Ehus are properly 

 chargeable to the free handling of this favorite flower. 



Poke-berry (Phytolacca decandra) is an irritant which affects chiefly 

 the mucous membranes. The green plant and the root are the parts 

 to be avoided. The mature stem and leaves seem to lose their irritat- 

 ing properties, but the root retains them throughout the life of the 

 plant. 



The Smartweeds (Polygonum) cause burning and itching of the 

 skin, which in some cases persists for a considerable time. The most 

 active forms in Indiana seem to be P. hydropiper and P. punctatum 

 Ell. (=P. acre H. B. K.) 



The Indian Turnips (Arisama triphyllum and A. Dracontium) are 

 violently acrid and almost caustic in every part. The mere handling 

 of these plants frequently produces intolerable itching and inflamma- 

 tion of the skin. 



The Skunk Cabbage (Spathyema fcetida) is harmless as to its leaves, 

 but the root is acrid and its handling is almost sure to produce itching 



