WEED MIGRATION 737 



AMERICAN WEEDS INTRODUCED INTO EUROPE. 



Every year more weeds are introduced into Europe from Amer- 

 ica; however, it is very noticeable that the more abundant of these 

 are from the warmer regions of America, rather than from the 

 colder regions. A good many of these are weeds of the open 

 country of North America. I have looked rather hastily through a 

 few of the floras of Great Britain, Italy, Austria and Germany, in 

 addition to a number of recent references on the adventive flora 

 of Europe, from which these data have been compiled. 



Apple of Peru (Nicandra pliysaloides) Germany (Garcke). 



Aster (Aster novi-helgii) Italy (Arcangeli), Germany (Garcke), 

 France (Acloque). 



Aster (Aster parviflorus) Germany (Garcke). 



Aster (Aster salicifolius) Germany (Garcke). 



Bug seed (Corispermum hyssopifolium) Germany (Garcke), 

 Italy (Arcangeli). 



Bur cucumber (Sicyos angulatus) Germany (Garcke), Italy 

 (Arcangeli) . 



Clotbur (Xanthium spinosum) Italy (Arcangeli), Germany 

 (Garcke, Bitter, Kiefer), Austria (Neilreich), France (Acloque). 



Collomia (Collomia grandiflora) Germany (Garcke). 



Cone flower (Rudbcckia hirta) Germany (Garcke). 



Cone flower (Rudbcckia laciniata) Germany (Garcke, Bitter, 

 Lehmann). 



Cone flower (Lepachys pinnata) Germany (Bitter). 



Evening primrose (Oenothera sinuata) Germany (Bitter). 



Fleabane (Erigeron annuus) France (Acloque), Italy (Ar- 

 cangeli). 



Fleabane horseweed (Erigeron canadensis) France (Acloque), 

 Austria (Neilreich), Germany (Garcke, Lehmann), England 

 (Hooker), Italy (Arcangeli). 



Galinsoga (Galinsoga parviflora) Italy (Arcangeli), Germany 

 (Garcke). 



Pigweed (Amaranthus retroflexus) Italy (Arcangeli), Germany 

 (Garcke, Alpers), France (Acloque), Austria (Neilreich). 



Goldenrod (Solidago canadensis) Germany (Garcke, Wegelin), 

 Austria (Neilreich). 



Goldenrod (Solidago lanceolata) Germany (Garcke), England 

 (Hooker). 

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