i 34 FLOWERS OF LAKES, RIVERS, ETC. 



The plant is dioecious, and the flowers are erect, white, large, 

 with a yellow patch at the base, and yellow anthers. The petals are 

 delicate, inversely egg-shaped. The Mowers spring in pairs from a 

 transparent membranous sheath at the base of the flower-stalk. Frog- 

 bit, however, does not always flower, and seldom produces any seed. 



The flower-stems are 3-4 in. Frogbit blooms in July and August 

 It is a herbaceous perennial, propagated by division. 



The flowers are dioecious and produced on the surface. The 



Photo. J. J. Ward 



FROGBIT (Hydrocharis morsus-ra/io', L. ) 



12 stamens are partly without anthers (3-6). The anthers are fixed 

 by the base. The plant is usually pollinated by the wind, but is largely 

 propagated by bulbils, being stoloniferous. In winter it is kept alive 

 by buds from the stolons or hibernacula. Honey is also secreted in 

 3 glands in the crown of the ovary or base of the petals, and is half 

 concealed, but insects do not often visit the flower. 



Ripe fruit is almost unknown. The manner of opening is irregular, 

 and the small seeds are blown out from their lightness. But the plant 

 does not often produce fruit and seeds, as it seldom flowers. 



The plant is aquatic, being a member of the floating-leaf association. 



Two beetles, Galeruca sagittarii and Donacia menyanthidis, are 

 found on it. 



