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11 



At. the present day, our close commercial relations with Great 

 Britain and the United States are producing a yearly influx of 

 these unwelcome visitors, and scattering them broadciist over the 

 country. Though new forms only now and then make their ap- 

 pearance, there is an incursion — renewed every summer to a 

 greater or less extern — of those familiar, self-made friends of 

 ours. At the same time, not only are these very species — along 

 with some members of our indigenous flora — migruting from 

 here and obtaining a footing in other foreign lands with 

 which we are in commercial intercourse, but they must fre- 

 quently reappear among their native brethren, in the countries 

 from which they originally came. Amongst those countries be- 

 tween which trade relations are intimate, there must be a con- 

 stant interchange in this way. 



Illustrative of this immigration from difterent countries, there 

 may be cited : from tropical America, Seuebura didi/m<t, Pers., 

 which occurs at Gaspe, and Montreal, and which has. probably, 

 been directly introduced, Chnuipodlum amhrosioidcs, L., species 

 of Amaranthus, of which there is presumption that they have 

 come by way of the United States, and Nicofiann ntsfloi, L., 

 which Dr. Gray considers a relic of cultivation by the Indians; 

 from the United States, Murtijnvi prohoscidni, Glos., probably 

 Acahipht Virghiica, L., and some of the Euphorbias, and from 

 Europe, in addition to many well-known plants, Potrntilla argen- 

 tcd, L., Leontodon autianntdc, L., Fbtntiujn btaccolata, L., Ru- 

 mex patlcntia, L., and (h/nodon Durfjjlou, Pers. 



The large yearly influx of population from different parts of 

 Europe aids materially in establishing species throughout the 

 Provinces, and the facilities afforded for the subsequent distribu- 

 tion of these species are especially great in consequence of the 

 long continuous lines of railway and water communication be- 

 tween the seaboard and all sections of the interior. Many intro- 

 duced plants arc thus of wide range. C'lpxdla harm pasforis, 

 Moench, Aihilha milhfoUani, L., Maruta cofidn, D. C, Ci/- 

 noglossuni officiiKdc, L., and Pidygonum pi;rsioirl'(, L., for ex- 

 ample, extend from Lake Superior to the Lower St. Lawrence. 

 Others, again, arc quite restricted in range. Leontodon autam- 

 nale, L., and Scnehicra didipna, Pers., are limited to the sea- 

 ports, and S. coronopus, D. C, is only known from Gaspe ; Ve- 

 ronica chamcedrys has not been observed elsewhere than at Que- 

 bec ; Sist/mbriu7n sophia, L., is uncommon in the Province of 



