432 THE ALISMA FAMILY. [Scheuchzerta. — 
In bogs and peaty marshes, in northern and Arctic Europe, Russian Asia, 
and North America, and here and there in the mountains of central Europe. 
In Britain, only in northern England, in Shropshire, and Methuen, near 
Perth. Fl. summer, rather early. 
———— 
VI. TRIGLOCHIN. TRIGLOCHIN. 
Tufted herbs, with linear, semi-cylindrical radical leaves, and leafless 
flower-stems, bearing a slender raceme or spike of small greenish flowers 
without bracts. Perianth of 6 nearly equal segments. Stamens 6, Ovary 
and fruit of 3 or 6 one-seeded carpels, each bearing a separate, small, 
feathery stigma, all united at first round a central axis, but separating from 
it when ripe. : 
A small genus, chiefly maritime, but widely distributed over the globe. 
Ripe fruit linear, with 3 carpels ‘ : : . . 1. TZ. palustre. 
Ripe fruit ovoid or oblong, with 6 carpels , ‘ . o« 2 TL. maritimum, 
1, T. palustre, tee (fig. 974). Marsh Trigléehin, Arrow-grass.— 
The tufted stock emits a few slender, creeping runners. Leaves slender, 
but rather succulent, varying from 2 to 8 inches in length, dilated and 
sheathing at the ne Flower-stems from 6 to 12 inches high, bearing in 
their upper half a slender spike of small, yellowish-green flowers, which are 
at first sessile, but as the fruiting advances the pedicels lengthen to 1 or 2 
lines, Perianth- segments broadly ovate, the feathery stigmas just appearing 
above them. After they fall off, the fruit lengthens to about 3 lines by less — 
than a line broad, tapering at the base; when ripe it separates from the 
base upwards into 3 carpels, leaving a central axis. 
In wet meadows, and marshes, and on the shallow edges of streams, more 
especially in maritime districts, in Europe, central and Russian Asia, and 
North America, extending from the Mediterranean to the Arctic regions. 
Common in Britain. Fl. all summer. 
2. T.maritimum, Linn. (fig. 975). Sea Triglochin.—Very near T, 
palustre, but usually rather stouter, with more succulent leaves, the flowers 
nearly similar ; but even in that state the ovary is broader, with 6 cells, and 
the ripe fruit is not more than 2 lines long, more than a line broad, and 
divides into 6 carpels. 
Generally more restricted to the vicinity of the sea than 7. palustre, but 
equally abundant with that species in the salt marshes of the northern 
hemisphere. Common in Britain. 7. from spring till autumn. 
LXXX. HYDROCHARIDEA. HYDROCHARIS FAMILY. 
Aquatic herbs, with undivided leaves, and mostly dicecious 
floweis, enclosed when young in an involucre or spatha of 1 to 
3 leaves or bracts. Perianth of 3 or 6 segments, either all petal- 
like or the 3 outer ones smaller and herbaceous, with a tube 
adherent to the ovary at its base in the females, without any 
tube in the males. Stamens in the males 3 to12. Ovary in 
the females inferior, 1-celled, with 3 parietal placentas, or divided 
into 3, 6, or 9 sells. Styles 3, 6, or 9, with entire or 2-cleft 
