FROM THE ATTACKS OF ANIMALS. 135 



secure their growth and increase; nay, he himself 

 assists their growth, and protects them at the cost 

 of much labor from the attacks of animals. But 

 only a very small proportion of the whole number 

 of plants are thus cared for by man ; the rest, from 

 which he receives no advantage, must find means 

 to protect themselves, or perish. These means of 

 protection, it is true, are all defensive, so that the 

 relation between plants and animals is not to be 

 compared to a state of war, but rather to an armed 

 peace. 



Nevertheless these defences are often dangerous 

 to the assailant, and they include poisons and 

 corrosive fluids, as well as sharp weapons. 



It is mysterious how grazing animals suspect the 

 existence of poison in leaves. Sometimes poison- 

 ous plants have a strong odor which is disagreea- 

 ble to men, as is the case with the Thorn-Apple 

 (Datura Stramonium)-, 1 but many others, which 

 are equally shunned by animals, have leaves which 

 are scentless to us, as long as they are unbruised, 

 like the Aconite, the Euphorbia, and the Gentians, 

 which are never eaten by wild animals, nor by 

 grazing flocks and herds. As long as they remain 



1 A good American example is the Skunk Cabbage (Symplocarpus 

 fuetidus') . 



