191.^] The Ottawa Naturalist. 51 



poisoning. Many experiments on man and other animals has 

 proved conclusively that no ill effect results from eating the 

 roots. The flowers and leaves do, however, sometimes produce 

 dermatitis when brought in contact with damp skin, some persons 

 are also affected by the carrot in the same way. 



One would hardly expect to find poisonous plants among 

 the EricacecB, but all the species of Kalmia are very poisonous, 

 and K. angustifolia, Sheep Laurel, and K. latifolia, Mountain 

 Laurel, destroy many sheep and cattle, and chickens are said to 

 have been poisoned by eating the vomited matter from poisoned 

 animals. The flesh of partridge is said to be rendered poisonous 

 when the birds eat the buds, and honey derived from the nectar 

 of the flowers appears to be poisonous. Many of the Solanaceous 

 plants are more or less poisonous, but the genus Solatium is the 

 onlv one that causes much injury. The berries of 5. nigrum, 

 Common Nightshade, are often cooked for food, but when green 

 are poisonous to man, and cattle are poisoned by eating the 

 leaves of either this species or S. Dulcamara. 



A few species of Composite are poisonous. Among these 

 Senecio Jacobaea has done the greatest damage, though its bad 

 effects on cattle seem so far to be confined to parts of Nova Scotia 

 and New Brunswick, where it is supposed to be the cause of what 

 is known as Pictou disease. It is most dangerous in its voung 

 state. Helenium autumnale also occasionally causes death when 

 eaten by cattle, and many genera such as Artemisia andTanacetum 

 are poisonous to man if the volatile oils are taken in large doses. 

 Eupatorium urticcefolium, White Snake Root, is generally believed 

 to cause the "trembles" in cattle, horses and sheep and milk 

 sickness in man. The trembles cause many deaths among 

 cattle, and butter and cheese made from the milk of affected 

 animals is poisonous to man. Until quite recently there seemed 

 to be no doubt that Eupatorium was responsible for the trembles, 

 but recent investigators do not believe this to be the case unless 

 it should be at times the carrier of some pathogenic organism. 

 The pollen of several composite plants such as ragweed, golden- 

 rod and chrysanthemum are said to cause hay fever. Ambrosia 

 artcmisiijolia is regarded as specially troublesome as an exciting 

 cause with reference to hay fever. There is as yet, however, no 

 conclusive proof that hay "fever is ever caused by pollen or that 

 pollen has any greater irritating effect on the air passages of 

 sensitive people than anv other dust of an organic character. 



In the discussion which followed the above review some 

 interesting observations were made as to the action of various 

 plants which were believed to produce poisonous effects in man 

 or beast. 



The common rhubarb was claimed bv Mr. White to be 



