256 POISONING. 



AMBROSIACE.E (ragweed FAMILY). 



Xanthium canadense. — The young seedlings of the American cock- 

 lebur are reported from Texas as being rapidly fatal to hogs. 



Xanthium spinosum. — The spiny clotbur is suspected of being poi- 

 sonous, but few cases have been definitely recorded against it. The 

 seeds apparently contain a toxic compound. 



Xanthium strumarium. — The young seedlings of the broad cock- 

 lebur are reported from Georgia as being fatal to hogs. Experiments 

 seem to show that the seed is poisonous. 



CARDUACE.E (THISTLE FAMILY). 



*Helenium autumnale.— Sneezeweed (sneezewort ; autumn sneeze- 

 weed; stagger weed; false sunflower) is found throughout the greater 

 portion of the United States, being most abundant in the Southern and 

 Eastern States. Sheep, cattle and horses that are unfamiliar with the 

 plant are often poisoned by it when driven to localities where it is abun- 

 dant. Stock avoid it, as a rule, but it is claimed that they sometimes 

 develop a taste for the plant, and are killed quickly by eating it in large 

 quantity. 



Senecio jacobaea. — The tansy ragwort, or stagger wort, is a European 

 plant which grows as a weed in ballast about New York and Philadelphia. 

 Farther north, in Nova Scotia, it has become extensively naturalised, and 

 it is there regarded by stock men as poisonous. It is interesting to 

 note that S. guadalcnsis of Mexico is also considered fatal to stock. 



COLCHICUM POISONING. 



Fodder of bad quality often contains leaves, flowers, and particularly 

 seeds of colchicum, which produce nausea, vomiting, colic and diarrhcea. 

 The colchicine acts particularly on the kidney and heart, producing 

 specific disturbance, indicated by hsematuria, polyuria, and cardiac pal- 

 pitation, with lowering of the body temperature. 



Even when poisoning is not fatal, it is very apt to produce abortion. 



POISONING BY ANNUAL MERCURY. 



Annual mercury given in green fodder is stated to produce indiges- 

 tion, diarrhcea, vesical and intestinal haemorrhage, and early death. 

 Some authors, however, deny that it has such toxic properties. 



POISONING BY BRYONY. 



In large doses all parts of the bryony plant are toxic — the root, stalk, 

 and leaves. 



