MARE’S-TAIL FAMILY 183


3. CatiftRicHE (Water Starwort).—Slender, submerged,
aquatic plants ; /eaves exstipulate, opposite, simple, entire, the
upper ones sometimes floating and often forming a rosette ;
flowers axillary, solitary, minute, moncecious, without calyx or
corolla, but usually with 2 white dvac/s beneath, consisting either
of one stamen, or very rarely two, with a slender f/ament and a
one-chambered anther dehiscing transversely, or of a 4-angled,
4-chambered ovary, with 2 slender styles ; fruct of 4-winged, 1-
seeded, indehiscent cocci. (Name from the Greek alos, beautiful,
thrix, hair.)

1. C. palustris (Spring Water Starwort).—Svems long, slender,
sending out long thread-like silvery roots from the joints; the
upper /eaves ovate-spathulate, floating in a light-green star-like


SSO EASES EE
SS ee


CALLITRICHE PALUSTRIS (Spring Water Starwort).
rosette, the stamens being the only parts of the plant actually above
water ; dracts straight, deciduous ; s¢y/es erect ; fruzt sessile, with
carpels swollen and bluntly keeled at the back.—Ponds and slow
streams ; common.—Fl. April—October. Annual or perennial.
2. C. stagndélis (Spring Water Starwort).—A terrestrial form,
with the upper eaves broad roundish, in a close rosette, or absent ;
bracts sickle-shaped, persistent ; s¢y/es erect in flower, reflexed in
fruit ; cavfels flattish, winged.—Chiefly on mud ; common.—F!.
May—September. Annual or perennial.
3. C. polymérpha, as yet only recognised in a few localities, is
similar, its dvacts being persistent ; but has s/zgmas 2—4 times as
long as the ripe fruit, and carvfel/s scarcely winged.
4. C. hamuldta, usually very small; /eaves mostly inear ;
bracts sickle-shaped, deciduous ; s¢y/es long, diverging ; carfels


184 ONAGRAR{E&


flattish with a blunt keel.— Marshes, lakes, and streams.—FI.
June—September. Annual or perennial.
