SCIENTIFIC NEWS. 7^ 



In pull Vi sib Ing- these jn<lo^ments and cllstribution of prizes 



for the year 1806, tlie academy proposes the following ques- 



ti6n for the present year 1807' 



Chemistry teaches us the means of discoverinsr the noxious Questioafcrf 

 . . . . . . Ib07. 



<|uahty of mineral bodies, whereas it is only empirically, 



that we have learned to distinguish poisonous plants from 

 those that are not so. Even the characteristics, by which 

 we think ourselves enabled to determine on the presence or 

 absence of poison in vegetables, are not always sufficiently 

 certain and incontestible. The livid colour, for example, 

 which has rendered many ])lants suspected, is a fallacious 

 sign. The burdock (arctium lappa) looks dull, and is of a 

 pale colour, yet it is a wholesome plant; on the contrary, 

 the laurel (daphne) is remarkable for the beauty of its 

 flowers and leaves, yet this is poisonous. The families of 

 ranunculus and anemone are as beautiful as they are nume- 

 rous ; they are however for the greater part noxious. The 

 same may be said of the disagreeable smell of plants, which 

 is taken for a diagnostic of the poisonous quality, and which 

 sign is equally uncertain with the preceding. The smell of 

 the laurel is very agreeable, while the stinking orach (che- 

 nopodinm vulvaria), an innocent and even salutary plant, is 

 of a very disagreeable smell. The smell of coriander is dis- 

 agreeable to many persons, yet it is of a very salutary na- 

 ture. The umbelliferous plants, that grow in wet and marshy 

 situations, have the reputation of being poisonous ; notwith- 

 standing this, the water parsnep, (sivmj and all its species, 

 the sison iimndatum ct suhtim, the phellandrium aquaficum^ 

 the angelica si/Ivestrts, the KEgopodium podagrariay plants 

 which thrive in marshes, contain no poison. It is plain, 

 therefore, that neither the livid colour, disagreeable smell, 

 nor growth in niarshy places, can furnish us with certain 

 and indisputable signs of the presence of poison in plants. 



The pretended repugnance of animals to pernicious plant* 

 is evidently as little "infallible. The division of plants, 

 madt/ by botanists, into classes, orders, and families, ac- 

 cording to tlieir nature, is not more effectual in discriminat- 

 ing those that are venomous. To be convinced of this we 

 have only to observe, that among the species of the night- 

 shade, a genus so much suspected, are found the potato 



(jolanum 



