RIVER-SIDE FLOWERS. 393 



The HAIRY MINT (M. hirsuta)Y\g. in " E. B.," 1030 is 

 a very common plant. The stem rises to three feet. The 

 leaves are green and hairy. The flowers are pale purple 

 in whorls. The flower-stalks are densely covered, parti- 

 cularly at their summits, with recurved, at times closely 

 pressed, white hairs. Flowers August and September. Tea 

 made of the green leaves of this species is excellent in 

 all nervous and hysterical cases. Mice have a particular 

 aversion to the smell of Mint. 



A water-plant has been unfortunately introduced into 

 this country which has increased to such an extent in many 

 localities as to completely block up the waterway in many 

 canals and slow-running rivers. This is the WATER-THYME 

 (Anacharis alsinastrum) Fig. in " E. B.," 1446 Elodea 

 Canadensis 'of Sowerby and other botanists, a native of 

 North America, supposed to be imported with some timber, 

 and first noticed in 1842 in the lake at Dunse Castle, 

 Berwickshire, by the late Dr. Johnston, and in 1847 by 

 Miss Kirby in the reservoirs of a canal in Leicestershire ; 

 then in the river White Adder, and by degrees extending 

 itself in all directions. It is a dark-green, much-branched 

 perennial, entirely floating under water, its flowers only 

 appearing above water for a short time at the period of 

 fertilisation. It has numerous leaves, which are either 

 opposite or in whorls of three or four without fore-stalks. 

 Its rapidity of growth is extraordinary. Immense masses 

 disfigure the shallows of the Trent and cover the bed of 

 the deeps. The stems are very brittle, and every fragment 

 is capable of growing. Waterfowl are very fond of it, and 

 by these means the seeds may be carried from one piece 

 of water to another. It is said that in some instances it 

 has been in such profusion and thickness as to impede the 

 ascent of the salmon ; but it certainly affords a shelter of 

 safety to many other kinds of fish. Fortunately swans 

 are extremely fond of it, and where it abounds it can be 

 almost eradicated by placing a pair of swans on the water. 

 In the Fishing Gazette appeared the following paragraph : 



" According to Dr. Brandes, of Hitzackes, Hanover, the 

 American weed Anacharis alsinas'.rum is, after all, an angel 



