666 PONTEDERIACE XEROPHYLLUM 
HETERANTHERA 
2 or 8, short: raceme loose, becoming 3-15 inches long, 30-40-flowered : 
pedicels 3-6 lines long, twice longer than the linear-lanceolate bracts and 
bractlets: segments of the perianth 3-4 lines long, a third longer than the 
stamens, bright yellow: filaments woolly except near the top: capsule ex- 
serted, the cells 10-15-seeded. In marshes in the Coast Mountains, south- 
ern Oregon and northern California. 
6 XEROPHYLLUM Michx. Fl. i, 210. (1803.) 
Tall perennial herbs with thick short woody rootstocks, coarse 
fibrous roots, simple erect leafy stems, narrow linear serrulate 
persistent leaves and many small white flowers in a terminal ra- 
ceme. Perianth of 6 distinct several-nerved persistent segments. 
Stamens 6, inserted at the base of the segments, with filiform- 
subulate filaments and rounded extrorse laterally dehiscent an- 
thers. Ovary sessile, ovate, 3-lobed, with 1-2 pairs of ovules in 
each cell. Capsule chartaceous, loculicidally dehiscent to the 
base, and sometimes also septicidal. Seeds 2-4 in each cell, as- 
cending, oblong, somewhat triangular-flattened, with thin longi- 
tudinally wrinkled, rather light-colored testa. 
X. tenax Nutt. Gen. i, 235. Rootstock often an inch thick or more: 
stems stout, 2-6 feet high, leafy below: radical leaves numerous, 1-3 feet 
long, about 2 lines wide. flat above, rather rigid; cauline leaves shorter, 
scattered, gradually reduced udward: racemes at first dense, elongating 
and becoming 1-2 feet long: lower bracts foliaceous and serrulate, the up- 
per scarious and often upon the lower part of the pedicel: pedicels an inc 
or two long, erect in fruit: segments of the perianth 4-5 lines long, scarcely 
equalling the stamens: styles 2 lines long: capsule broadly ovate, acute, 
nearly 3 lines long, 3-valved: seeds narrowly oblong. Common in the high 
mountains, California to Brit. Columbia and Idaho. ' 
X. Douglasii Watson Proc. Am. Acad. xiv, 284. ‘‘ Pedicels shorter, 
(6-15 lines long) : flowers smaller, the segments (24 lines long) exceeding 
the stamens: styles a line long: capsule cordate-ovate, 2 lines long, 6-valved, 
the abruptly acute cells separating and then dehiscing: seeds shorter and 
broader. Oregon to Montana. ”’ 
OrpER XCIX PONTEDERIACE Dumort. Fam. 59. (1829) 
Perennial aquatic or bog plants with grass-like or petioled 
thick leaves and perfect more or less irregular solitary or spiked 
flowers subtended by lesf-like spathes, Perianth free from the 
ovary, corolla-like, 6-parted. Stamens 3 or 6, inserted on the 
tube or the base of the perianth: filaments filiform, dilated at 
base or thickened at the middle: anthers 2-celled, linear-oblong 
or rarely ovate. Ovary 3-celled with the placenta in the axis, 
or 1-celled with 3 parietal placente. Style filiform or columnar, 
with terminal entire or minutely toothed stigma. ovules ana- 
tropous, numerous, sometimes only one of them perfect. Fruit 
a many-seeded capsule or 1-seeded utricle. Embryo central, ° 
cylindrical, in copious albumen. 
1 HETERANTHERA R. &P, Prodr. Fl. Per. 9. (179+.) 
Herbs with creeping, ascending or floating stems, grass-like or 
petioled leaves and small yellow, white or blue flowers subtended 
