An Illustrated Flora of the Northern United States, Canada and the British Possessions/Marsileaceae
Perennial herbaceous plants rooting in mud, with slender creeping root-stocks and 2- or 4-foliolate or filiform leaves. Asexual propagation consisting of sporocarps borne on peduncles which rise from the rootstock near the leaf-stalk or are consolidated with it, containing both megaspores and microspores. The megaspores germinate into prothallia which bear mostly archegonia, while the microspores grow into prothallia bearing the antheridia.
Three genera and some 60 species of wide distribution known as Pepperworts.
Marsh or aquatic plants, the leaves commonly floating on the surface of shallow water, slender-petioled, 4-foliolate. Peduncles shorter than the petioles, arising from their bases or more or less adnate to them. Sporocarps ovoid or bean-shaped, composed of two vertical valves with several transverse compartments (sori) in each valve. [Name in honor of Giovanni Marsigli, an Italian botanist, who died about 1804.]
About 53 species, widely distributed. Besides the following 2 or 3 others occur in Texas.
|•||Sporocarps glabrous and purple when mature.||1.||M. quadrifolia.|
|•||Sporocarps densely covered with hair-like scales.||2.||M. vestita.|
|2. Marsilea vestita Hook. & Grev.|
Hairy Pepperwort. Fig. 86.
M. vestita Hook. & Grev. Ic. Fil. pl. 159. 1831.
Rootstocks slender, creeping. Petioles slender, 2'-5' high; leaflets similar to those of the preceding species, entire or toothed; sporocarps 2"-4" long, 2"-3" wide, with a short raphe, a short and blunt lower tooth and an acute and sometimes curved upper one, densely covered with soft spreading narrow hair-like scales or (in the forms known as M. mucronata) these short and appressed or almost wanting; sori 6-11 in each valve.
In wet sand or in shallow ditches, Florida to Kansas, Arizona and Mexico, California and British Columbia.