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TJrtica dioica, Roman nettle; Triticum repens, couch grass. 

 These and man}' others seem to follow in the wake of 

 civilization. The Urtica dioica followed the Romans from 

 Italy ; and being found where they had their encamp- 

 ments, it is known as the Roman nettle. It is not diffi- 

 cult to divine how it got over. Perhaps among the hay 

 used by the Pilgrim fathers in packing their utensils on 

 board the Mayflower it was secreted. From a single 

 plant the downy seed would be wafted and spread rapidly. 

 I saw it to-day growing on a rubbish heap. Although 

 some of these plants are perfect pests to the farmer, yet 

 they may sometimes be found to possess qualities which 

 may make them valuable, even worthy of cultivation. 

 The whole plant of Genista tinctoria, woad waxen, root, 

 stem, leaf and flower, dyes yellow. Mixed with Isatis 

 tinctoria, woad, which has also found its way over, it dyes 

 green, while the woad itself, like indigo, dyes blue. With 

 these two plants the ancient British tatooed their bodies. 

 The Triticum repens, couch grass, makes a paper very 

 superior to that made from the straw of any other grass, 

 and would be used extensively if it could be got in quan- 

 tity. Even Urtica dioica, the Roman nettle, has been 

 found lately to contain a fibre in its tissues, stronger and 

 more abundant than that got from the Cannabis sativa, 

 hemp, and may come to be extensively used in the manu- 

 facture of ropes. In riding along this morning I was 

 admiring the Salix alba, white willow. A gentleman sit- 

 ting by me said "it is a useless wood." I did not contra- 

 dict him, but I remembered the wonderful antiseptic 

 properties of the salicylic acid got from the willow, which 

 is likely to make this wood of great value. This acid is 

 perfectly wholesome, without either taste or smell. A 

 merchant in Hamburgh has found that fish impregnated 

 with it will keep perfectly fresh for twenty days. 



