84 SCHEUCHZERIACEAE. 
2. SCHEUCHZERIA L. Sp. Pl. 338.1753. 
Rush-like bog perennials with creeping rootstocks, and erect leafy stems, the leaves 
elongated, half-rounded below and flat above, striate, furnished with a pore at the apex and 
a membranous ligulate sheath at the base. Flowers small, racemose. Perianth 6-parted, 
regularly 2-serial, persistent. Stamens 6, inserted at the base. of the perianth-segments ; 
filaments elongated; anthers linear, basifixed, extrorse. Ovaries 3 or rarely 4-6, distinct or 
connate at the base, 1-celled, each cell with 1 or 2 collateral ovules. Stigmas sessile, papil- 
lose or slightly fimbriate. Carpels divergent, inflated, coriaceous, 1-2-seeded, follicle-like, 
laterally dehiscent. Seeds straight or slightly curved, without endosperm. [Name in honor 
of Johann Jacob Scheuchzer, 1672-1733, Swiss scientist. ] 
A monotypic genus of the north temperate zone. 
1. Scheuchzeria palustris L. 
Scheuchzeria. (Fig. 187.) 
Scheuchzeria palustris I,. Sp. Pl. 338. 1753- 
Leaves 4’-16/ long, the uppermost reduced to 
bracts ; stems solitary or several, usually clothed 
at the base with the remains of old leaves, 4/—10’ 
tall; sheaths of the basal leaves often 4’ long with 
a ligule 14’ long; pedicels 3/’—10’’ long, spreading 
in fruit; flowers white, few, in a lax raceme; per- 
ianth-segments membranous, I-nerved, 114’’ long, 
the inner ones the narrower; follicles 2’’-4’’ long, 
slightly if at all united at the base; seeds oval, 
brown, 214’’-3’’ long with a very hard coat. 
In bogs, Labrador to Hudson Bay and British Co- 
lumbia, south to New Jersey, Pennsylvania, Wisconsin 
and California. Also in Europe and Asia. Summer. 
Family 5. ALISMACEAE DC. Fl. Franc. 3: 181. 1805. 
WATER-PLANTAIN FAMILY. 
Aquatic or marsh herbs, mostly glabrous, with fibrous roots, scapose stems 
and basal long-petioled sheathing leaves. Inflorescence racemose or paniculate. 
Flowers regular, perfect, monoecious or dioecious, pedicelled, the pedicels ver- 
ticillate and subtended by bracts. Receptacle flat or convex. Sepals 3, per- 
sistent. Petals 3, larger, deciduous, imbricated in the bud. Stamens 6 or 
more ; anthers 2-celled, extrorse or dehiscing by lateral slits. Ovaries numerous 
or rarely few, 1-celled, usually with a single ovule in each cell. Carpels be- 
coming achenes in fruit in our species. Seeds uncinate-curved. Embryo horse- 
shoe shaped. Endosperm none. Latex-tubes are found in all the species, 
according to Micheli. 
About 13 genera and 65 species, of wide distribution in fresh water swamps and streams. 
Carpels in a ring upon a small, flat receptacle. 1. Alisma. 
Carpels crowded in many series upon a large convex receptacle. 
Flowers perfect, staminate or polygamous. 
Pedicels not recurved ; calyx spreading. 
Pedicels recurved in fruit ; calyx appressed to the carpels. 
Flowers monoecious or dioecious. 
1. ALISMA I.. Sp. Pl. 342. 1753. 
Perennial or rarely annual herbs with erect or floating leaves, the blades several-ribbed, 
the ribs connected by transverse veinlets, or seemingly pinnately veined. Scapes short or 
elongated. Inflorescence paniculate or umbellate-paniculate. Flowers small, numerous on 
unequal 3-bracteolate pedicels, the petals white or rose-tinted. Stamens 6 or 9, subperigy- 
nous. Ovaries few or many, borne in one or several whorls on a small flat receptacle, ripen- 
ing into flattened achenes which are 2—3-ribbed on the curved back and 1-2-ribbed on the sides. 
{Greek, said to be in reference to the occurrence of the typical species in saline situations. ] 
About ro species, widely distributed in temperate and tropical regions. Only the following are 
known to occur in North America. 
Stamens 6, strongly compressed; flowers panicled. 1. A. Plantago-aquatica. 
Stamens 9, turgid; flowers umbelled. 2. A. tenellum. 
. Echinodorus. 
Lophotocarpus. 
. Sagttiaria, 
Son 
