82 FLOWERS OF LAKES, RIVERS, ETC. 



so far as is known, nor any insects. Water snails are fond of it, e.g. 

 Limnesa^ Planorbis, Succinia, &c. 



The old generic name Nasturtium, given by Pliny, is derived from 

 nasus, nose, tortus, twisted, in reference to the hot character of the 

 plant. 



The English names are Billers, Brooklime, Brown Cress, Carsons, 

 Water Crashes, \Vater Cress, Eker, Water and Well Grass, Water 

 Kerse, Rib, Teng-tongues, Well Grass, Well Kerse. 



The plant was said to drive warts away if laid on them. The 

 Greeks used it as a salad and as a medicine. Pliny says it was used 

 for brain troubles. In England it was first cultivated in 1801 or 

 1808. An aromatic oil which it contains renders it nutritive. The 

 mineral salts which the plant contains render it nutritive. 



Water Cress requires running water, and, when cultivated, plants 

 are bedded at intervals, in rows in the direction of the current. The 

 beds should be kept free from mucl and other plants, and occasionally 

 thinned out. 



ESSENTIAL SPECIFIC CHARACTERS: 



24. Radicula Nasturtium aquaticum, Rendle and Britten. Stem 

 branched, erect, succulent, leaves bipinnate, lower larger, leaflets rounded, 

 dentate, flowers white, twice as long as calyx, pod linear, curved. 



Great Yellow Water Cress (Radicula amphibia, Druce) 



This has not been found in a fossil condition. It is a native of the 

 Warm Temperate Zone, found in Europe, North Africa, and Tem- 

 perate Asia. In England it is found in Somerset, Wilts, Dorset, 

 Sussex, the whole of the Thames province, as well as in Anglia, 

 throughout the Severn and Trent provinces, in Montgomery in Wales, 

 but not in Mid Lanes. It is found in the Mersey district, throughout 

 the H umber district, and in Durham. It is naturalized in a few parts 

 of Scotland, as in Dumfries, and occurs in Ireland. 



Like its congener the Water Cress, the Great Yellow Cress is an 

 aquatic plant, half hydrophyte, half a land plant, being amphibious, as 

 the Latin specific name indicates. It is fond of damp watery places, 

 and very often grows luxuriantly and tall in rivers and canals, or in 

 lakes. It has been united with Horse Radish, a plant which, likewise, 

 though terrestrial enough in our gardens, where it is difficult to eradi- 

 cate it, is found more or less wild by water. 



The habit of this plant is much more like that of Water Cress than 

 any other plant which grows in water, but it is more rigid, more erect, 



