102 FISH CULTURE. 



the soil suited to it, &c. &c. ; we have shows and 

 prizes for the best specimens of agricultural pro- 

 ductions, and thousands of persons assemble to note 

 and study them ; but who ever thinks of acclimatizing 

 an apparently worthless water- weed ? 



Now all plants, even to the meanest looking weed, 

 have their uses for man ; and among the fauna of the 

 world, there must be many which would be valuable 

 to us in the light above indicated. We have received 

 one from America — the alsinastrum. This weed has 

 hitherto been a terrible nuisance, growing so rapidly, 

 as to fill up and choke our smaller rivers, in many 

 instances, in an incredibly short time ; but it might 

 be that this weed, so troublesome and so difficult to 

 eradicate in the south, would be a great benefit to the 

 hill and moor lakes of the hard north. Hardy water 

 plants, in which insects can thrive, are greatly wanted 

 there ; and it might be found that the introduction of 

 the alsinastrum, and its attendant insects, would have 

 a very favourable effect on the size and flavour of the 

 trout found in such places. I do not of course say 

 that this is so, but I merely suggest the possibility 

 in order to point out how such designs could be 

 carried out. It would in time become a very interest- 

 ing and valuable fact, to hear that Mr. So-and-so had 

 brought home a new water-weed, favourable to the 



