2. VALLISNÈRIA, L. Tape-grass. Eel-grass.
Flowers strictly diœcious; the sterile numerous and crowded in a head on a conical receptacle, enclosed in an ovate at length 3-valved spathe which is borne on a very short scape; stamens mostly 3. Fertile flowers solitary and sessile in a tubular spathe upon an exceedingly lengthened scape. Perianth (calyx) 3-parted in the sterile flowers; in the fertile with a linear tube coherent with the 1-celled ovary, but not extended beyond it, 3-lobed (the lobes obovate); also 3 linear small petals. Stigmas 3, large, nearly sessile, 2-lobed. Ovules very numerous, scattered over the walls, orthotropous. Fruit elongated, cylindrical, berry-like.—Stemless plants, with long linear grass-like leaves, wholly submerged. The staminate clusters being confined to the bottom by the shortness of the scape, the flower-buds themselves break from their short pedicels and float on the surface, where they shed their pollen around the fertile flowers, which are raised to the surface by sudden growth at the same time; afterwards the thread-form scapes (2–4 feet long) coil up spirally, drawing the fruit under water to ripen. (Named for Ant. Vallisneri, an early Italian botanist.)
1. V. spiràlis, L. Leaves linear, thin, long and ribbon-like (1–6° long), obscurely serrulate, obtuse, somewhat nerved and netted-veined.—Common in slow waters, N. Eng. to Fla., west to Minn. and Tex.
3. LIMNÒBIUM, Richard. American Frog's-bit.
Flowers diœcious, (or monœcious?) from sessile or somewhat peduncled spathes; the sterile spathe 1-leaved, producing about 3 long-pedicelled flowers; the fertile 2-leaved, with a single short-pedicelled flower. Calyx 3-parted or cleft; sepals oblong-oval. Petals 3, oblong-linear. Filaments entirely united in a central solid column, bearing 6–12 linear anthers at unequal heights; there are 3–6 awl-shaped rudiments of stamens in the fertile flowers. Ovary 6–9-celled, with as many placentæ in the axis, forming an ovoid many-seeded berry in fruit; stigmas as many as the cells, but 2-parted, awl-shaped.—A stemless perennial herb, floating in stagnant water, proliferous by runners, with long-petioled and round-heart shaped leaves, which are spongy-reticulated and purplish underneath; rootlets slender, hairy. Sterile flowers rather small; the fertile larger; peduncle nodding in fruit. Petals white? (Name from λιμνόβιος, living in pools.)
1. L. Spóngia, Richard. Leaves 1–2´ long, faintly 5-nerved; peduncle of sterile flower about 3´ long and filiform, of the fertile only 1´ long and stout.—Stagnant water, N. J. to Fla.; also L. Ontario, Ill., and Mo.
Order 109. BURMANNIÀCEÆ. (Burmannia Family.)
Small annual herbs, often with minute and scale-like leaves, or those at the root grass-like; the flowers perfect, with a 6-cleft corolla-like perianth, the tube of which adheres to the 1-celled or 3-celled ovary; stamens 3 and distinct, opposite the inner divisions of the perianth; capsule many-seeded, the seeds very minute.—A small, chiefly tropical family.
1. BURMÁNNIA, L.
Ovary 3-celled, with the thick placentæ in the axis. Filaments 3, very short. Style slender; stigma capitate-3-lobed. Capsule often 3-winged. (Named for J. Burmann, an early Dutch botanist.)