264 Flowers and their Pedigrees. 



ably useful to the plants which bear them ; and, if we 

 find their usefulness ridiculous, that Is a peculiarity of 

 our own sense of humour which in no way affects the 

 abstract truth of the observation. It is impossible, 

 in fact, that a plant should not benefit by having its 

 berries poisonous, and so some plants must necessarily, 

 in the infinite variability of nature, acquire the property 

 of killing their friendly allies. It has been asked 

 why the birds have not on their side learnt that the 

 arum is poisonous. The very question shows at once 

 an ingrained inability to understand the working of 

 natural selection. Every bird that eats arum berries 

 gets poisoned : but the other birds don't hold a 

 coroner's inquest upon its body or inquire into the 

 cause of death. Naturally the same bird never eats 

 the berries twice, and so experience has nothing more 

 to do with the matter than in the famous illogicality 

 about the skinning of eels. 



There are many other curious points of interest 

 about the arum : there are the glossy arrow-headed 

 leaves ; there is the sharp, deterrent, pungent juice ; 

 the tall, succulent, biting stem ; the thick, starchy, 

 poisonous rootstock, where the plant lays by the store 

 of nutriment it collects each summer for ne.xt spring's 

 flowering season. All these demand and repay the 

 minutest and most careful stud v. I^ut life is too 



