ANIMALS AND POISON 77 



as a drug becomes so much diluted before it reaches 

 the last or true digestive stomach. Half an ounce of 

 black shag tobacco is often given to cattle as a vermi- 

 fuge, and though in such a case the animal's tempera- 

 ture falls slightly, and its pulse is rather slow for a 

 few hours, it feeds as usual and appears to feel no 

 inconvenience. 



In common with human beings, animals seem to 

 be affected by poison in certain forms when in a par- 

 ticular condition of health. At other times they can 

 eat the same plant or shrub with impunity. In certain 

 states of health a man can eat pork, lobsters, cockles, 

 scallops, and other somewhat risky foods without bad 

 effects. At other times the same edibles would pro- 

 duce on him the effect of slight ptomaine poisoning. 

 Two persons may eat of the same food at the same 

 time, and while one is perfectly well afterwards, the 

 other may become- violently ill. The curious cases of 

 yew poisoning among cattle or horses seem to be some- 

 what analogous. They will sometimes browse on shoots 

 of yew and take no harm whatever. At other times 

 they are obviously made very ill, or die, from eating 

 the leaves. They have even been found dead with the 

 yew fresh and undigested in their stomachs. Where 

 poisonous plants are present in any great numbers in 

 herbage, it seems quite impossible to prevent cattle 

 from eating them. The " poison veldt " of parts of the 

 Transvaal has a particularly bad reputation caused by 

 plants one of which is said to be a species of tulip 

 which come into leaf in the spring. 



In addition to the poisons mentioned above, the 



