TETRADYNAMIA— SILIQUOSA. Sisymbrium. 195 



4. N. amp/iibium. Amphibious Yellow Cress. Great 



Water Radish. 



Leaves oblong, pinnatifid, or serrated. Roots fibrous. Pe- 

 tals longer than the calyx. Pod elliptical. 



N. amphibium. Br. in Ait. H. Kew. v. 4. 1 10. DeCand. Syst. v. 2. 

 196. Comp.ed.4.\\2. Hook. Scot. 201. 



Sisymbrium amphibium. Linn. Sp. PL 9 17' TVilld. v. 3. 491. Fl. 

 Br.702. Engl.Bot.v.26.t.l840. Fl. Dan. t. 984. 



5. (not Nasturtium) palustre repens latifolium majus. Mich. Hort. 

 Flnrent. 89. 



Radicula n. 486. Hall. Hist. v.\.2\\. 



R. sylvestris seu palustris. RaiiSyn. 301 ; but not of J. Bauhin. 

 Raphanus aquaticus. Ger. Em. 240. f. 

 R. aquaticus alter. Bauh. Prodr. 38. f, good. 

 R. sylvestris officinarum aquaticus Lob. /c. 319./. 

 Broad Water Radish. Petiv. H. Brit. t. 49. f. 8, 

 /3. Raphanus aquaticus. Bauh. Hist. v. 2. 867./. 

 Great Jagged Water Radish. Petiv. H. Brit. t. 49./. 10; copied 

 /rom Bauhin. 



In rivers, ditches, and places about their banks, not constantly 

 overflowed, frequent. 



Perennial. June — August. 



Roots long and stringy, perpendicular, not creeping, but throwing 

 out numerous fibres, such as proceed from the lower parts of 

 the trailing or floating, wide-spreading, leafy, striated, not much 

 branching, stem. Leaves generally smooth, but occasionally 

 downy when growing in dry situations ; the lowermost on long 

 stalks, deeply pectinated under water, otherwise elliptic-lanceo- 

 late, cut, or serrated ; upper ones sessile, or clasping, oblong, 

 pectinated, serrated, or nearly entire, all varying greatly accord- 

 ing to the depth of the water, or strength of the current ; on 

 such plants as grow entirely out of the water, the leaves are 

 smaller, broader, and merely serrated. Fl. small, bright yellow, 

 plentiful, in aggregate clusters. Pet. always longer than the 

 calyx. Pods usually small and abortive, roundish, tipped with 

 the style often as long as themselves. 



This plant is noticed by the celebrated M. Chateaubriand, in his 

 account of England, for its wonderful powers of increase by root. 

 He observed it in the river near Beccles, where he long resided as 

 an emigrant, and his rather florid description has excited wonder 

 and curiosity in many, who daily, perhaps, pass over, without 

 regard, several no less interesting works of their Creator. Some 

 of M. DeCandolle's references belong to the foregoing. 



334. SISYMBRIUM. Hedge^mustard. 



Linn. Gen.338. Juss. 239. Fl. Br. 700. Comp. ed. 4. 108. Br. 

 in Ait. H. Kew. v. 4. 1 11 . DeCand. Syst. v. 2. 458. 



o2 



