18 BOTANY. 
with radical leaves, equitant and sheathing at the base, and scaly heads of 
flowers. Natives chiefly of tropical regions, having no important properties. 
There are about six genera and seventy species. Examples: Xyris, Abolboda, 
Philydrum. Four or five species of the typical germs Xyris are known in the 
United States. 
OrvER 22. PonTEDERIACE#, the Pond-weed Family. Perianth tubular, 
colored, six-parted, more or less irregular; sestivation circinate. Stamens 
three to six, perigynous ; anthers introrse ; ovary free, or slightly adherent, 
three-celled ; ovules numerous, anatropal; style one; stigma simple. Fruit 
a three-celled, three-valved capsule, with loculicidal dehiscence. Seeds 09, 
attached to a central axis ; testa membranous; hilum small; embryo straight, 
in the axis of somewhat mealy albumen; radicle next the hilum. Aquatic or 
marsh plants with sheathing, parallel-veined leaves, which are sometimes 
cordate or sagittate, and have inflated petioles. The flowers are spathaceous. 
They are natives of North and South America, East Indies, and Africa. 
Their properties are unimportant. There are six genera, according to Lind- 
ley, and thirty species. The principal genera of the United States are Ponte- 
deria, Heteranthera, Schollera, and Syena. 
OrpER 28. GiLuiesiace#, the Gilliesia Family. Perianth six-parted, 
sometimes five-parted by cohesion of two of the pieces, in a double row; 
the outer, petaloid and herbaceous; the inner, smaller and more colored ; 
eestivation twisted. Stamens in a double series; cuter whorl sterile, in the 
form of a six-toothed urceolate body, or of scale-like bodies, one of which 
forms a sort of labellum; inner whorl of six stamens, of which three are some- 
times sterile. Ovary superior, three-celled ; style one; stigma simple. Fruit 
a three-celled, three-valved capsule, with loculicidal dehiscence. Seeds nu- 
merous, attached to the axis; spermoderm black and brittle; embryo curved 
in the midst of fleshy albumen. Herbs with tunicated bulbs, grass-like leaves, 
and umbellate spathaceous flowers. Natives of Chili. Examples: Gilliesia, 
Miersia. € 
OrperR 24. Metantruaces, the Colchicum Family. Perianth petaloid, 
in six pieces, which are sometimes slightly coherent, usually involute in eesti- 
vation. Stamens six; anthers extrorse. Ovary three-celled; ovules nume- 
rous; style three-parted; stigmas three, undivided. Fruit a three-celled 
capsule, with septicidal or loculicidal dehiscence. Seeds with a membranous 
spermoderm ; albumen dense, fleshy ; embryo very minute. Plants with bulbs, 
tubers, or fibrous roots, having parallel-veined leaves, sheathing at the base. 
The flowers are sometimes polygamous. They are natives of various parts of 
the globe, but are most abundant in northern countries. 
Sub-order 1. Uvulariee, Bellworts. Perianth early deciduous, sepals 
distinct, petaloid. Styles united into one at the base or throughout. Fruit a 
three-celled few-seeded berry or loculicidal pod. Stems from small perennial 
root stocks and fibrous roots, forking, bearing ovate or lanceolate, membrana- 
ceous, sessile or clasping leaves, and perfect flowers; peduncles solitary or 
one-flowered. Examples: Uvularia, Prosartes, Streptopus. | 
Sub-order 2. Colchicee. Rhizome bulbous, dehiscence of pod septicidal. 
Of the typical genus Colchicum, the European species, C. autumnale (pi. 
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