82 THE SCOTTISH NATURALIST 



doubtful whether reproduction of the species would be 

 perceptibly accelerated, for every fragment of leaf or stem 

 that is broken off and floats away is the founder of a new 

 colony. 



This beautiful weed — for it is beautiful both in form and 

 colour — behaves in British waters in a manner peculiar to 

 itself. In ordinary seasons it forms a close green carpet 

 over the bottom of the lake or stream ; but at long intervals 

 of years it rushes into rampant growth so as completely 

 to fill considerable sheets of water. A few years ago, I 

 forget how many, one such uprush of Elodea took place in 

 Lochleven, and despairing anglers wrote to the newspapers 

 complaining that the fishing of that famous loch was ruined 

 for ever, unless means could be taken to eradicate the weed. 

 I replied by a letter in the Scotsman newspaper, assuring 

 the anglers that their occupation was not gone, only 

 suspended, for that Elodea never remained in this rampant 

 condition for more than two consecutive seasons, after which 

 it would retire to the bottom and lie low until the soil it had 

 exhausted recovered its virtue. Such proved to be the 

 case in Lochleven, which I believe to be now quite as fishable 

 as ever. 



I have had occasion to note the behaviour oi Elodea in 

 the White Loch of Myrtoun, a sheet of water within the 

 park of Monreith. In the summers of 1895 and 1896 there 

 was a tremendous growth of this weed, which disappeared 

 from the surface during the winter of 1906-7, and ceased to 

 be conspicuous or troublesome till the spring of 191 3 when 

 a fresh uprush took place. In that summer much of the 

 surface was blocked with floating masses of its stems and 

 foliage and remains so to the present time; but I expect 

 the precedent of 1895-6 will be followed, and that the water 

 will be clearer than ever by the end of spring. For these 

 visitations leave this good effect behind them — every other 

 waterweed, such as the troublesome ]\Iyriop]iylhiin, is choked 

 into insignificance. 



The American pond-weed is highly nutritious ; cattle 

 are very fond of it ; I have often seen them browsing 

 greedily upon it in the Hampshire chalk-streams. But the 



