404 ILLUSTRATIONS OF THE NATURAL ORDERS. 



Compound ovary five-celled; stigmas sessile. Capsule bursting 

 clastically by five valves. Seeds several, without albumen, and with 

 a thick straight embryo. — Ex. Impatiens, the Balaam, or Touch- 

 me-not. Remarkable for the elastic force with which the capsule 

 bursts in pieces, and expels the seeds. Somewhat differently irreg- 

 ular blossoms are presented by the 



785. Ord. TropCDOlacCie {Indian- Cress or Nasturtium Family). 

 Straggling or twining herbs, with a pungent watery juice, and peltate 

 or palmate leaves. Flowers irregular. Calyx of five colored and 

 united sepals, the lower one spurred. Petals five ; the two upper 

 arising from the throat of the calyx, remote from the three lower, 

 which are stalked. Stamens eight, unequal, distinct. Ovary three- 

 lobed, composed of three united carpels ; which separate from the 

 common axis Avhen ripe, are indehiscent, and one-seeded. Seed 

 filling the cell, without albumen: cotyledons very large and thick. — 

 Ex. Tropceolum, the Garden Nasturtium, from South America, 

 where there are a few other species, one of which bears edible tubers. 

 They possess the same acrid principle and antiscorbutic properties 

 as the Cruciferae. The unripe fruit of Tropseolum majus is pickled, 

 and used as a substitute for capers. 



786. Ord. LimnanthaCCDE differs from the last only in its regular and 

 symmetrical blossoms, and the erect instead of suspended seeds ; the 

 calyx valvate in aestivation. — Ex. Limnanthes of California (some- 

 times cultivated as an ornamental annual), and Flocrkea of the 

 Northern United States. 



787. Ord. OxalidaCCBC ( Wood-Sorrel Family). Low herbs, with an 

 acid juice, and alternate compound leaves ; the leaflets usually ob- 

 cordate. Flowers regular, of the same general structure as in Li- 

 naceae, &c., except the gynaecium, which in fruit forms a membra- 

 naceous five-lobed and five-celled, several-seeded capsule. Seeds 

 with a fleshy outer coat, which bursts elastically when ripe, with a 

 large and straight embryo in thin albumen. — Ex. Oxalis, the 

 Wood-Sorrel. The herbage is sour, as the name, denotes, and con- 

 tains oxalic acid. The foliage is remarkably sensitive in some spe- 

 cies. The tubers of some South Amei-ican species, filled with starch, 

 have been substituted for potatoes. 



788. Ord. Zygophyllacea; differs from the last in the opposite, 

 mostly abruptly pinnate leaves, distinct stamens (the filaments com- 

 monly furnished with an internal scale, Fig. 379), and the styles 

 united into one. — Ex. Tribulus and Kallstrcemia (introduced into 



