r 5 6 



FLOWERS OF LAKES, RIVERS, ETC. 



Like many other aquatic plants, the aerial stem is a scape with 

 many sword-shaped, long leaves surrounding it, and giving it a grass- 

 like habit. The leaves are 3-sided, spongy, twisted, and very sharp, 



Photo. II. Irvin- 



FLOWERING RUSH (Butomus umbellatus, L.) 



hence the first Greek name. The base of the stem is reddish, like 

 the flower-stalks also. The leaves are sheathed at the base. 



The scape is smooth, round, bearing a single umbel of large 

 numerous flowers (20-30 in an umbel), rose-colour, red, purple, the 

 perianth-segments oblong at first with 4 grooves, then more or less 

 heart-shaped. The bracts have a membranous margin. The involucre 



