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THE GUIDE TO NATURE. 



the soil and are borne by the wind over so-called Russian thistle, nearly allied to 



the fields until a knoll, rock or some the perfectly harmless salt-weed that 



other impediment causes their arrest, grows along our seashore. 



The worst one of these, and it has ap- Given these natural means of distribu- 



peared but recently in the east though tion, and there are many more contriv- 



extremely common in the west, is the ances, it still remains a problem how 



ONLY A WEED— MILKWEED. 



