POISONOUS PLANTS 161 



Toxicity. — According to Cornevin, tlie lethal doses ia 

 grammes per kilogramme body weight are — 



Horse, 7 (equivalent to about 50 grains per pound). 

 Dog, 18 (equivalent to about 130 grains per pound). 



Ruminants and birds are less susceptible. 



Symptoms. — In the horse there is dilatation of the pupils, 

 vertigo, uncertain gait, and trembling. The subject falls, 

 the body is cold and extremities stiff, respiration laboured, 

 pulse slow and small, and there are convulsive movements 

 of the head and limbs. There is rapid enfeeblement, and 

 death within thirty hours. No special lesions beyond a little 

 intestinal irritation are seen. This account is abridged 

 from experiments quoted by Cornevin, in which 4 pounds 

 of the grains were given to a horse. 



According to the same authority, the yellow ether extract 

 of the grain appears to act as a hypersesthetic, causing sali- 

 vation and vomition, trembling, convulsions, and tetanic 

 rigidity. The water extractive displays anaesthetic and 

 narcotic properties, causing drowsiness, coma, prostration, 

 and lack of co-ordination in movements, as well as saliva- 

 tion and vomition. 



A case of the poisoning of pigs through the admixture of 

 L. temulentum grains with barley dressing was noted by 

 Taifc.* There were foaming, convulsions, and paralysis ; 

 the stomach and intestines were inflamed, and the lungs 

 congested. 



As regards maize, which is but rarely cultivated in Great 

 Britain, the dangerous properties seem to be confined to 

 the male flowers, and result in urinary disturbance, a fine 

 yellow powder being passed or concreting to calculi. Dis- 

 ease from this cause is very unlikely to be met with in 

 ordinary practice, but in South Africa the male flowers are 

 reputed to produce poisoning, though it is also suggested 

 that the results may be due to fatal tympanites, following 

 an excessive feed. But it should be remembered that young 

 maize is capable of generating prussic acid. In consideration 



* Veterina/rian, 1842, p. 212. 



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