802 



THE HYDROCHARTS FAMILY. 



Fig. 965. 



In ponds, canals, and slow streams, 

 abundant in North America, and pro- 

 bably introduced from thence into Bri- 

 tain, where it was first observed in 1847, 

 in Yorkshire, Leicestershire, and near 

 Berwick and Edinburgh. It has since 

 spread with great rapidity over many 

 parts of England, especially in the canals 

 of Lincolnshire and Cambridgeshire. Fl. 

 summer and autumn. 



II. FROGBIT. HYDROCHARIS. 



A single species, distinguished as a genus from Stratiotes and others 

 more by its habit than by any very marked characters in the flower. 



1. Common Frogbit. 



Hydrocharis Morsus-ranse, Linn. 

 (Fig. 966.) 



(Eng. Bot. t. 808.) 



Stems floating, resembling the runners 

 of creeping plants, with floating tufts of 

 radical leaves, peduncles, and submerged 

 roots. Leaves stalked, orbicular, en- 

 tire, cordate at the base, rather thick, 

 about 2 inches diameter. Peduncles of 

 the male plant rather short, bearing 2 

 or 3 rather large flowers on long pe- 

 dicels, enclosed at the base in a spatha 

 of 2 thin bracts. Outer segments of the 

 perianth pale green, shorter and nar- 

 rower than the inner white ones. Sta- 

 mens 3 to 12. Female spatha sessile 

 among the leaves; the flowers like the 

 males, but with the pedicel enlarged at 

 the top into a short perianth-tube en- 

 closing the ovary. Styles 6, with 2-cleft 

 stigmas. Fruit dry, 6- celled, with se- 

 veral seeds. 

 In ditches and ponds, dispersed over Europe and central and Eus- 

 sian Asia, but not extending to the Arctic Circle. Occurs in many 



Fig. 966. 



