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from the ordinary routes of travel, and are mistaken by the col- 

 lector for genuine indigenes. From these original stations they 

 have spread with such rapidity that it has been very difficult 

 for the few collectors scattered over this vast area to keep pace 

 with them. I hope at some future time to present a somewhat 

 exhaustive study of these introduced members of the flora of 

 Oregon. In the present paper I desire to confine myself to 

 calling attention to one of the "ports of entry" for these immi- 

 grants, and to show in what numbers they are finding lodgment 

 on our soil at that point. 



Every student of plant-life who has collected near the coast 

 has observed what a prolific field for the introduction of new 

 species is afforded b\' the heaps of ballast-material that are 

 found in the neighborhood of the larger seaports. For one 

 season at least, species from all parts of the world are mingled in 

 wild confusion. Those indigenous to the tropics usually do not 

 survive their first winter, and many others are mere waifs. 

 appearing perhaps in considerable abundance for a single season, 

 but disappearing entirely after their first flowering. Many 

 others, however, more tenacious of life, or with vegetative organs 

 better adapted to the struggle with new and adverse conditions, 

 beconie fully established, and from the original point of introduc- 

 tion rapidly distribute themselves to all parts of the neighboring 

 region. Several distributing points of this sort occur about the 

 ports of the Pacific coast; and it has been my good fortune 

 during the past two seasons to study one of the most interesting 

 of these ballast-grounds. Lying along the left bank of the 

 Willamette River at Linnton, seven miles from the heart of 

 the city of Portland, and covering an area of some 40.000 square 

 yards between the river and the tracks of the North Bank 

 Railroad, is an old ballast-dump, now little used, that has 

 remained undisturbed long enough to become covered with a 

 dense growth of vegetation, nearly all of which is foreign, though 

 near the edges a few native species have gained a footing. 

 Many different "strata" of ballast can still be traced, and each 

 has its own characteristic flora, though the more vigorous species 

 have spread indiscriminately over the entire area. Much of 



