1869.] DRUMMOND — ON SPREADING PLANTS. 883 



Montreal and at Lennoxville. It is indigenous on the north 

 shore of Lake Superior, and during the past summer I found it 

 entwining itself among the shrubs which border Salmon Creek, in 

 the Township of Melbourne, Province of Quebec. It can no 

 longer be regarded as a plant of purely Western range. 



Festiica ovina, Gray, var durmsada, Gray. 



Poa compressa, L. 



P. pratensis, \i. 



Agrostis vulgaris, With. 



Panicum glabrum, Gaudin. 



P. crusgalli, L. 



Triticum repens, L. 



T. caninum, L. 



So intimately connected in their range and habits with the 

 exotic plants of our fields and roadsides, are our native species 

 in their abnormally diffused states that there seems a propriety 

 in referring to them here. Their habits are instructive as they 

 furnish an explanation of the circumstances which have led to 

 the introduction of foreign plants into the country in our times. 

 Native species, when they assume these rambling habits — as 

 most, if perhaps not all, of our domesticated exotics to a greater 

 or less extent have in the countries from which they have come 

 — frequently stray into grain-fields, to roadsides, wharves, and 

 other localities, whence their seeds are readily conveyed to 

 foreign lands, ; long with grain, wool, packing, personal effects of 

 emigrants, ballast, and other means of transmission, so amply 

 afforded. Thousands of the seeds thus yearly brought to 

 foreign shores probably never germinate, and of those which do, 

 perhaps but a small proportion, representing some of these hardy 

 species, and a few others, which find a congenial climate and soil, 

 mature and perpetuate their existence. The recurring immigra- 

 tion, year after year, of the same as well as occasional other 

 species, soon, however, gives a feature to the vegetation there. 

 The spreading habits of any of the plants, in the countries from 

 which they have come, will have hardened their natures, and nerved 

 them for not only enduring the vicissitudes of, perhaps, dissimilar 

 soils, and a more trying climate, but also of encroaching upon 

 the domains of the native vegetation. In this manner has, I 

 conceive, arisen in a large measure the distribution of the exotic 

 flora of our roadsides and fields. And it further seems unques- 

 tionable that those members of our indigenous flora which have 



