12 



Quebec and quite unknown west of Prescott, and Plantago 

 media, L,, has, as yet, only been observed at Toronto. 



Currents may play a more important part in the introduction 

 of exotic plants than is generally supposed. Our Canadian lake 

 coas-ts supply illustrations of this agency at work. Coral islands 

 are, it is well known, mantled with a vegetation largely resulting 

 from the seeds carried to their shores through the medium of 

 winds and currents. In the United Kingdom, the influence of 

 the Gulf Stream is observable in the occurrence of Eriocaulon 

 gtptdiHjnhtre, With., Si'<jji'iiichluni (tncrpa, Car., and Naias ficxllts, 

 liostk, upon the western coasts. It seems, indeed, possible that 

 the part played by this great current in the phenomena of distri- 

 bution has not been brought into sufficient prominence. 'J he evi- 

 dence, though limited, suggests the enquiry whether, in addition 

 to .some local plants, others, common to the two continents, and 

 fairly diflPuscd, at fne present day, in Europe, may not have had 

 their starting points on its west shores, whither their seeds have 

 been carried, by the Gulf Stream, from America, at stray times, 

 during passing centuries, without destroying their vitality. 



