454 



EXOGENOUS OR DICOTYLEDONOUS PLANTS. 



monium), and the Bittersweet (Solanum Dulcamara) ; the last 

 only slightly narcotic. Yet the berries of some Solanums are eat- 

 able when cooked (as Tomatoes, the Egg-Plant, &c.), and the 

 starchy tubers of the Potato are an important article of food. But 

 the fruit and seeds of Capsicum (Cayenne pepper) are stimulant. 



850. Ord, Gentianaceae (the Gentian Family). Herbs, with a 

 watery juice ; the leaves opposite and entire. Flowers regular, 

 often showy. Calyx of usually four or five persistent, more or 

 less united sepals. Corolla mostly convolute in aestivation ; the 

 stamens inserted on its tube. Ovary one-celled, with two parietal, 

 but often introflexed, placenta ; styles united or none. Capsule 

 many-seeded. Seeds with fleshy albumen and a minute embryo. 

 Ex. Gentiana, Frasera (the American Columbo). A pure bit- 

 ter and tonic principle (Gentianine) pervades the whole order. 

 Gentiana lutea of Middle Europe furnishes the officinal Gentian, 

 for which almost any of our species may be substituted. 



851. Subord, Menyantlli'eiB (the Buckbean Family] has alternate, 

 sometimes trifoliolate or toothed leaves, and a valvate-induplicate 

 aestivation of the corolla. Ex. Menyanthes, Limnanthemum (this 

 bears the peduncles on the petiole, Fig. 949). 



943 



947 946 942 948 945 944 



852. Subord, Obolarieae has an imbricative aestivation of the CO- 

 FIG. 942. Flower of Gentiana angustifolia. 943. Corolla, and 944, the calyx, laid open. 



945. The pistil. 946. Cross-section of the pistil, showing the parietal attachment of the ovules. 



947. Ripe capsule of G. Saponaria, raised on a stipe : the persistent withering corolla, &c., torn 



away. 94S. A magnified seed, with its large and loose testa. 949. Leaf of Limnanthemum 



(ViUarsia), bearing the flowers on its petiole. 



