256 
POIiYPETALOUS OEDEKb. 
Pig. 180. 
sessile. Fruit a capsule, bursting 
elasticallj by five valves. Seeds 
numerous, destitute of albumen ; em- 
hryo straight. 
a. Properties : chiefly remarkable for the 
elastic force with which the valves separate at 
maturity and expel the seeds. 
Genus. — Impatiens. 
Fig. 180, a, is a branch both in flower and 
fruit ; h, diagram of the flower brought into its 
true position with respect to the axis, the trans- 
verse line underneath showing the position of 
the bract. 
428. TuopjsoLACEiE, the Indian Cress Trite. — ^Trailing or 
twining herhs. Leaves alternate, without stipules. Segals 3-5, 
colored, the lower one spurred. Petals equal or unequal. Sta- 
mens 6-10, distinct. Ovary composed of 3 or 5 carpels ; o-rfoles 
solitary, erect or pendulous. Fruit indehiscent, the pieces sep- 
arable from a common axis. Seeds large, destitute of albumen, 
filling the cell in which they lie ; embryo large ; cotyledons 
large, thick, and consolidated. 
a. Properties : some plants of this order produce edible tubers ; they possew 
the same acrid principle and antiscorbutic properties as the Cruciferae. 
Genera. — 1. Trop^eol^ — Flowers irregular ; ovules pendulous — Tropseoiuin. 
2. LiMNANTH^ — Flowers regular ; ovules erect — Limnanthes, Florkea. 
429. GEEANiACEiE, the Geranium Tribe. — Herbaceous plants 
or shrubs. Leaves simple, either opposite, or alternate with 
peduncles opposite to them, mostly with stipules. Sepals 5, 
persistent, more or less unequal, aestivation imbricated. Petals 
5, unguiculate, mostly convolute in aestivation. Stamens iO^ 
monadelphous. Ova/ry composed of Fig. isi. 
6 carpels ; ovules solitary, pendulous ; 
styles 5, cohering round the axis. Fruit 
composed of five 1-seeded carpels, each 
terminated by an indurated style, 
which curls from the base upward 
carrying the pericarp along with it. 
Seeds exalbuminous, wath a curved 
folded embryo ; cotyledons leafy, con- 
volute, and ]3laited together, 
rt. Properties : the roots are simply and strong- 
ly astringent ; the foliage abounds with an aro- 
matic resinous matter and an ethereal oil. 
Genera. — Geranium, Erodium, Pelargonium, 
Oplotheca. 
Fig. 181, a. Geranium maculatum; h, the calyx 
and corolla removed, showing the 10 monadelphous stamens and the cohering 
