LECTURE XXVI. 

 POISONOUS PLANTS. 



POISON HEMLOCK, (Coaium maculatum). 



Description. — This plant came to the United States from 

 Europe or Asia. It is now naturalized and quite common in 

 the eastern and middle states, but not very common in the Mis- 

 sissippi Valley. It is smooth, i. e., not hairy or mealy. The 

 stem is hollow; more or less spotted with purple, and the plant 

 is a biennial, growing two to seven feet high. The leaves re- 

 semble those of parsley, and the flowers grow in showy white 

 clusters, appearing in July and August. The leaves have a dis- 

 agreeable flavor, and the odor, especially from crushed leaves, is 

 also disagreeable. 



The poison. — The active poison is a volatile alkaloid known 

 as conine, found in the seeds and leaves. The root is less dan- 

 gerous in March, April and May, but becomes very poisonous 

 later in the season. 



This plant does not usually grow in great numbers in any 

 one pasture or field, but is very actively poisonous, so that it 

 does not require the eating of large quantities to insure fatal 

 results. 



Symptoms. — The symptoms are those of gradual and pro- 

 gressive weakening, especially a loss of physical strength. Sight 

 is affected, but the mind is said to remain clear. Death results- 

 from pulmonary paralysis. In poisoning from water hemlock 

 there are usually present convulsions which do not appear in the 

 case of poisoning from the true poison hemlock. The symptoms, 

 of poisoning in cows are especially the profuse flow of saliva,, 

 bloating, lack of appetite, feebleness and weak pulse and severe- 

 pain. 



BROAD LEAF LAUREL, IKalmia latifolia). 



Commonly called laurel, sometimes mountain laurel, poison 

 laurel, sheep laurel, and sometimes poison ivy. 



Vet Studies— 7. 



Digitized by Microsoft® 



