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Paul railroad and can well account for the line of introduction. 

 It soon spread to various localities in and around Chicago, though 

 I did not see it in the locality where I reside till 1900. In 1903 

 I found it common by the side of the Lake Shore and Michigan 

 Southern railroad at Dune Park, Ind., thirty-five miles east of 

 here. It is a quite common weed in the waste grounds of Chi- 

 cago now. In Beal's Michigan Flora the first date given for a 

 locality is Benton Harbor, 1896. This is on the east side of 

 Lake Michigan, nearly opposite Chicago. The entry is also 

 made, "later in many localities." As the Gray's New Manual 

 states that it is " locally abundant as a pernicious weed " it may 

 be considered as quite generally spread throughout the northern 

 parts of the United States and the southern part of Canada. 

 Since Britton and Brown give it a place as a ballast plant at New 

 York, there may also be other centers of migration from eastern 

 harbors, but the main line has evidently been from the northwest. 

 The spreading of this weed has been quite rapid, gaining a 

 large area in about twenty years. It produces seeds in great 

 abundance. As I have observed it the height does not generally 

 exceed 5 to 8 dm., that is, not very tall as one might infer from 

 its specific name, though the stature is more or less influenced 

 by the character of the soil. When crowded by its own kind or 

 by other growths it may be very slender and but little branched, 

 but with ample room it is bushy-branched, the diameter equaling 

 or exceeding the height, or of a somewhat globular form, Hke a 

 tumble-weed. Whether it actually functions as such I have seen 

 no case, but the shape is one that suggests that it could be easily 

 rolled by the wind if loosened from the ground by any means. 

 These are the possibilities of a tumble-weed. 

 Chicago, Illinois 



