ACTION OF CONIUM AND CONINE 429 



affected by conium. The convulsions occurring in conium 

 poisoning appear, nevertheless, to be of central origin, 

 although consciousness is retained until the stage of asphy- 

 xia. The special senses are somewhat interfered with (sight). 

 The motor cells of the inferior cornua are slightly depressed 

 by methyl-coniine, which influences the cord as well as the 

 motor nerves, but it is considerably less active than coniue. 

 The muscles are primarily unaffected. 



Eye. — The pupil is dilated (not constantly) and ptosis 

 is observed in poisoning by conium, owing to paralysis of 

 the oculomotor nerve endings. If conine is dropped into 

 the eye, primary contraction, due to reflex irritation, is soon 

 succeeded by dilatation of the pupil. 



Bespiration. — The spinal and medullary respiratory 

 centres are finally depressed by lethal doses of conium, and 

 this result, together with paralysis of the terminations of 

 the nerves of the diaphragm, causes death by asphyxia. 



Elimination. — Conine is excreted by all channels, but 

 mainly in the urine. 



Toxicology. — The minimum fatal dose of conium is un- 

 certain, owing to the proneness of the alkaloid to decompo- 

 sition, and to the volatility and the variable amount con- 

 tained in the crude drug. A few drops of the alkaloid will 

 kill small cats and dogs. Herbivora, as goats, sheep and 

 horses, are less susceptible than carnivora. 



The domestic animals occasionally become accidentally 

 poisoned by eating hemlock at pasture. The symptoms 

 exhibited are dulness, loss of muscular power (at first in 

 the hind legs), stumbling and falling, or lying down. "We 

 observe, also, nausea, salivation (sometimes amaurosis), 

 dilatation of the pupil and ptosis, sweating, and often mus- 

 cular tremors and clonic convulsions. The pulse becomes 

 slow and feeble, the breathing faint, the surface cold and 

 clammy, and the animal often lies as still as though dead, so 

 complete is the paralysis. Death finally occurs from asphy- 

 xia, frequently associated with coma. The respiration ceases 

 before the heart-beat. The urine of poisoned animals may 



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