38 Umbelliferae [ch. 



Horse 0-100 per cent, of the live weight. 



Ox 0-125 



Sheep 0-200 



Pig 0-150 



Eabbit 2-000 



Holmes described Oenanthe crocata as the most dangerous and 

 virulently poisonous of all our native plants {Pharm. Jour., 1902). 



Other species of Oenanthe are also poisonous in a less degree — 

 e.g. 0. fistulosa L., and 0. Phellandrium Lamk. 



Toxic Principle. Poehl (1895) obtained from the root of this species 

 an amorphous neutral product which he designated Oenanthotoxin. The 

 latest investigation is that by Tutin, who examined entire dried plants 

 collected in early spring, and the experiments confirmed the conclusion 

 arrived at by Poehl, that the toxic principle is a neutral resin. A dark- 

 coloured, viscid resin, insoluble in water, and equal to 3 per cent, of the 

 weight of the plant, was extracted, and it is stated that the neutral 

 portions of the petroleum and ether extracts of this resin represent the 

 toxic principle of the plant. As there is no evidence of the homogeneity 

 of this product, and it is probably complex in character, it was given no 

 name or formula. The fact that it has poisonous properties was ascer- 

 tained by administering the various products to guinea pigs per os. 



Symptoms. In poisoning by 0. crocata the symptoms generally 

 appear very quickly, and in serious cases death may follow in from one 

 hour to a few hours. In Tutin's experiments on guinea pigs the extracts 

 referred to above rendered the animal hypersensitive in two to four 

 hours, while marked convulsions, with trismus soon appeared; the 

 heart-beat became very noticeably slow and the convulsions persisted 

 until death ensued. There is great restlessness, difficult breathing, 

 convulsions, loss of sensation, blindness and stupefaction (Miiller); 

 Lander says the symptoms recall hemlock poisoning, with the addition 

 of green foetid diarrhoea. 



In cattle, one hour after eating, there is depression and accelerated 

 respiration; the conjunctivae are injected, the eye turns in its orbit, 

 the pulse is weak but rapid, and there is foaming. Later, there is 

 colic, and spasmodic contractions of limbs and jaws. If the quantity 

 ingested is sufficient to cause death, the animal falls, but still moves 

 its limbs. There is bellowing, contraction of pupils, insensibihty, and 

 death in convulsions — or, if not fatal, cattle may remain paralysed. 



In the horse, the appearance of the symptoms and the course of the 

 illness are much more rapid and the nervous symptoms are accentuated. 



