XANTHIUM SPINOSUM: LINN^US. 643 



seeds were first carried to these countries from Europe, attached to 

 the coats of the sheep and cattle which the Spanish colonists brought 

 with them from their native land, where the plant is indigenous. 



On this northern continent, according to Dr. Gray, the Xanthium 

 spinosum grows in waste places on the sea board and along rivers 

 southward, and he quotes it doubtfully as naturalized from Tropical 

 America. Whilst it is possible that the plant may have thus reached 

 the United States, there is yet another way by which the seeds are 

 constantly being introduced into that country, viz., in the wool which 

 is very extensively imported thither from South America, and more 

 particularly from Buenos Ayres. Rarely could a fleece of wool from 

 this latter place be met with, without some of the Xanthium burrs 

 sticking to it, and in the preparation of this wool for use, every 

 woollen mill becomes a centre for the dispersion of the seeds. Pro- 

 bably, by this means, the sporadic appearance of this plant in Canada 

 may be explaiued, as a woollen mill formerly stood at Dundas, near 

 the place in which the plants are now found. 



Although the climate of Western Canada may prove sufliciently 

 rigorous to prevent the growth of this noxious weed, save in sheltered 

 localities, yet it would be a wise step to endeavour to eradicate it 

 whilst it is yet confined to a limited district, and before it becomes 

 thoroughly acclimatized. 



