36 



Umbelliferse • [ch. 



UMBELLIFEB^. 



Cowbane or Water Hemlock {Cicuta virosa L.). This plant is 

 undoubtedly exceedingly poisonous, and fatal cases have occurred in 

 both man and farm live stock. It has been mistaken by man for parsley, 

 celery or parsnip, with fatal results, many persons having succumbed 

 to it. The rootstock is attractive to children on account of its sweetish 

 taste. Pott says that either fresh or dry it is poisonous to all animals 

 when only a small quantity is eaten, and often causes rapid death. 

 Sheep and goats appear to be less readily affected than other domestic 

 animals, and cattle to be most sensitive. The loss of eleven animals in 

 Brittany was noted in the Veterinarian in 1877, and a number of cattle 

 died in Ireland (Veterinary News, 1911), death in both cases being due to 

 Cowbane. It is clearly dangerous to grazing animals which have easy 

 access to it, especially if ordinary herbage is scarce. Hedrick (Canada) 

 is quoted as stating that a piece of the root about the size of a walnut 

 is sufficient to Mil a cow in about fifteen minutes ; and MliUer says that 

 the quantity of dried plant sufficient to kill a horse appears to be about 

 lib. According to Kanngiesser the mortality in human poisoning due 

 to this plant amoimts to 45 per cent, of the cases. 



Toxic Principle. The poisonous character of Cowbane has not 

 been fuUy investigated, and the toxic principles are given as the alkaloid 

 Cicyutine, with Oil of Cicuta, and Cicutoxine. The last is a bitter resinous 

 substance classed by Cushny in the picrotoxin group ; it occurs in the 

 dry root to the extent of 3'5 per cent. The toxicityis stated to vary 

 with season and chmate ; the rootstock is most poisonous in spring. 



Symptoms. In man the yellow poisonous juice in the rhizome induces 

 epileptic convulsions, followed by death. The cicutoxine gives acrid 

 narcotic symptoms quickly followed by fatal results. The symptoms 

 usually appear within two hours, and death ensues in half-an-hour 

 to several hours. The symptoms which appear in an hour or so are 

 given as loss of appetite, saUvation, vomiting (in swine), nausea, colic 

 (in horse), bloating (in cattle), diarrhoea, irregular pulse and heart, 

 dilatation of pupils, rolling of eyeballs, vertigo, reeling in circles, twisting 

 of neck, falling down, automatic movement of limbs, opening and 

 shutting of mouth, and death, usually with convulsions, in from half 

 an hour to an hour after first inanifestation of symptoms. 



For cattle, Lander gives hurried respiration, collection of froth at the 

 mouth and nostrils, and tympanites. The limbs are extended and 

 alternately stiffened and relaxed. 



