192 MEDICINAL AND POISONOUS PLANTS 



poisonous quantity into the blood through a scratch or other 

 sUght wound in the skin. 



The plants which produce alkaloids or other poisons would 

 seem to be protected against the ravages of herbivorous 

 animals by means of these substances. All such animals, 

 however, are not affected alike by them. Thus cattle eat 

 poison-ivy without harm, and various insects are known to 

 feed exclusively upon plants which are deadly poisons to 

 higher animals. Commonly jjoisons are associated with rank 

 .odors or disagreeable tastes, but in some poisonous plants 

 which are avoided by cattle and sheep there are no such 

 warnings that we can chscover. In the plant's economy the 

 substances in question are to be considered simply as by- 

 products which are sometimes protective. It is a curious fact 

 that many plants may he poisoned 1)j' their own alkaloids. 

 For example, an opium poppy is killed if watered with a 

 solution of morphine. 



62. Plants poisonous to eat. The number of poisonous 

 plants AA'hich are to be found growing wild or in gardens is 

 much larger than is generally supposed, and the cases of 

 jjoisoning annually reported are more numerous than is 

 commonly realized. While it will not be possible for us to 

 deal with all the species that are dangerous, it will be sufficient 

 for our pur]5ose to select for special consideration those which 

 have proved most likel}' to cause injury. A knowledge of 

 these kinds, and of the ways in which poisoning by them has 

 occurred, is not only highly important in itself as a means of 

 safety, but will lead to certain rules of general application. 

 It will be convenient for us to group the cUfferent kinds ac- 

 cording to the parts which are most dangerous. Neverthe- 

 less it must be understood that when any part of a i^lant is 

 poisonous every other part is to be regarded with suspicion. 



One of the most connnon ways in which poisoning occurs 

 is from the eating of unfleiyjrounrl jxnis of plants which re- 

 semble more or less closely species that are known to be 

 edible. Thus it has often happened that young folks off for 

 a ramble in th(> country come across some wild ]ilant that 

 suggests parsnip or some similar herl) and has an attractive 

 looking root which has perhajis been uncovered by recent 



