ANIMALS AND POISON 73 



It is an interesting question whether the native Somali 

 camels really avoided the dangerous plants, or whether 

 they had become " immune " by eating them for gene- 

 rations, as cats and their kittens which have eaten snake 

 poison are believed to become protected from the effects 

 of a snake bite. But the probability is all in favour of 

 the theory that they purposely avoid and reject what 

 they instinctively know to be poisonous. If the food 

 is pleasant and plentiful, there is no reason to believe 

 that animals ever cease eating until they think they 

 have had enough, and by that time it would probably 

 be too late for them to make use of experience on a 

 later occasion. 



Whatever be the reason for the fact, "warning" 

 notices of various kinds are frequently affixed by 

 Nature to poisonous plants, almost as legibly as the 

 label which the law insists that chemists shall place 

 upon poisonous drugs. Many of the poisonous fungi 

 have an odious smell, so much so that no mammal or 

 bird ever thinks of touching them. On the other 

 hand, the scent of the mushroom is distinctly appetis- 

 ing and pleasant. Henbane, an exceptionally poisonous 

 and quite beautiful wild plant, has a most unpleasant 

 scent which is instantly detected by cattle when the 

 plant is green. They most carefully avoid touching 

 it when growing. But it seems to lose its warning 

 odour when dried in hay. Instances have been quoted 

 in which it has been injurious to cattle when consumed 

 in this form. The common "fool's parsley," which 

 has poisonous seeds, is not, we believe, eaten by any 

 bird; neither do cattle touch it when growing in 



