CL. IX.] 14. BUTOMUS UMBELLATUS. 373 



ries. The goldsmiths also use the powerful acid of this berry 

 to give silver a white colour, because the copper, with which 

 silver is alloyed, is soluble in it, 



CLASS IX. 

 14. 



Butomus iimbellatus. 



Blumenbinse, Deutsches Blumenrohr, Wasserviole. — French, 

 Jonc Jleuri. — ^Ital. Giunco Jlorido, — Engl. Floivering Rush, 

 — Swed, Bhmwass. 



This beautiful plant grows in our streams, pools, and other 

 deep waters. The root is a horizontal lying tuber, about the 

 thickness of a thumb, frequently still thicker, covered with a 

 blackish rind, from which the fibres of the root, about the 

 thickness of pack-thread, pass downwards, and the flower- 

 shoots rise upwards. The leaves spring from the tuber ; 

 they are triangular below, but towards the point they be- 

 come flat ; throughout nearly their whole length they are of 

 the same size ; and though their length is about four or five 

 feet, they are scarcely an inch broad. 



Between these leaves, and surrounded by them, rises the 

 round, even flower-stalk, four, five, and six feet high, and 

 about the thickness of a finger. This contains a white, spon- 

 gy pith, which consists of a compound cellular texture, and 

 shews some scattered bundles of spiral vessels. At the top of 

 the stalk stand the flowers in an umbel, which contains about 

 fifteen flowers on stalks ; and at its base there is a membra- 

 naceous sheath of four, five, and six membranaceous, dry, 

 pointed leaves, which contained the flower before its evo- 

 lution, but after it has flowered are reflex. The flower 

 consists of six ovate, rose-coloured petals, which externally 

 are of the nature of a calyx, and have slits ; but internally 

 are of the nature of a corolla, and have the requisite integu- 



