LXXX. HYDROCHARIDEA, 433 
stigmas. Fruit small, ripening under water, indehiscent, 
Seeds several, without albumen. 
A small Order, widely diffused over the globe. 
Stem floating and branched, with small opposite or whorled 
leaves. Female perianth-tube long and thread-like. Stigmas3 1. ELopEA,. 
Stem root-like, with floating tufts of orbicular leaves. Female 
perianth-tube short, on a slender pedicel. Stigmas6 . . 2 HyDRocHARIS. 
Stem scarcely any. Leaves tufted, succulent, radical. Female 
perianth-tube short, on a stout pedicel. Stigmas 6 . . 3&. STRATIOTES. 
I. ELODEA. ELODEA. 
Stems submerged, branched, and leafy. Flowers sessile, the males with 
3-9 stamens, the females with a long, thread-like jperianth-tube. Style 
adherent to the tube, with 3 notched or lobed stigmas. Ovary 1-celled, 
with 3 parietal placentas. . 
A small genus, temperate and tropical. 
1, EB. canadensis, Michx. (fig. 976). Canadian Hlodea.—A dark 
green, much branched submerged perennial. Leaves numerous, opposite 
or in whorls of 3 or 4, sessile, linear-oblong, transparent, 3 or 4 lines long. 
Flowers sessile in the upper axils, in a small, 2-lobed spatha ; the slender 
perianth-tube of the female often 2 or 3 inches long, so as to attain the 
surface of the water, where it terminates in 3 or 6 small, spreading 
segments. Anacharis Alsinastrum, Bab. 
In ponds, canals, and slow streams, abundant in North America, and 
introduced from thence into Britain, 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, and there are 
now but few counties without it. 2. summer and autumn. 
Il. HYDROCHARIS. FROGBIT. 
A single species, distinguished as a genus from S¢ratzo¢es and others 
more by its habit than by any very marked characters in the flower. 
1. H. Morsus-ranze, Linn. (fig. 977). Common Frogbit.—Stems 
floating, resembling the runners of creeping plants, with floating tufts of 
radical leaves, peduncles, and submerged roots. Leaves stalked, orbicular, 
entire, cordate at the base, rather thick, about 2 inches diameter. Pedun- 
cles of the male plant rather short, bearing 2 or 3 rather large flowers on 
long pedicels, enclosed at the base in a spatha of 2 thin bracts. Outer 
segments of the perianth pale green, shorter and narrower than the inner 
white ones. Stamens 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 enclosing the ovary. Styles 6, with 2-cleft stigmas. 
Fruit dry, 6-celled, with several seeds. 
In ditches and ponds, dispersed over Europe and central and Russian 
Asia, but not extending to the Arctic Circle. Occurs in many parts of 
England and Ireland, not indigenous in Scotland. 47. summer. 
Ill. STRATIOTES. STRATIOTES. 
A single species, with the flowers nearly of Hydrocharis, but a succulent 
fruit, and a very different habit. 
3 Ff 
