EXOGENOUS OK DICOTYLEDONOUS PLANTS. 



435 



ovuled, with one perfect cell and two abortive ones. Fruit a kind 

 of acheniura. Seed suspended, exalbuminous. Embryo straight, 

 radicle superior. — Ex. Valeriana, the Valerian, and Fedia, the Lamb- 

 Lettuce : the latter is eaten as a salad. The perennial species, 

 especially the roots, exhale a heavy and peculiar odor, have a some- 

 what bitter, acrid taste, and are antispasmodic and vermifugal. 

 Valerian of the shops is chiefly from Valeriana officinalis of the 

 South of Europe. It produces a peculiar intoxication in cats. The 

 large roots of V. edulis are eaten by the aborigines of Oregon. 

 The famous Spikenar-d of the ancients, esteemed as a stimulant 

 medicine as well as a perfume, is the root of a Nardostachys of the 

 Himalayas. 



843. Ord. Dipsacea; {Teasel Family). Herbs, with opposite or 

 whorled sessile leaves, destitute of stipules. Flowers in dense 

 heads, which are surrounded by an involucre. Limb of the adnate 

 calyx cup-shaped and entii'e or toothed, or forming a bristly or 

 plumose pappus. Corolla tubular ; the limb four- or iive-lobed, some- 

 wdiat irregular. Stamens four, distinct, or rarely united in pairs, 

 often unequal, inserted on the corolla. Ovary one-celled, one-ovuled. 

 Seed suspended, albuminous. — Ex. Dipsacus, the Teasel, and 

 Scabiosa, or Scabious. AH natives of the Old World. Teasels are 

 the dried heads of Dipsacus fullonum, covered with stiff and spiny 

 bracts, with recurved points. 



844. Ord. CompositlB (Composite or Sunflower Family). Herbs 

 or shrubs ; Avith the flowers in heads (compound flowers of the 



887 



older botanists, 394, Fig. 323-325), crowded on a receptacle, and 

 surrounded by a set of bracts (scales) forming an involucre ; the sep- 

 arate flowers often furnished with bractlets (chaff, palece). Limb of 

 the adnate calyx obsolete, or ^pappus (Fig. 5G9-573), consisting 



PIG. 887. A bead of flowers of Cichory (Fig. 323) vertically divided. 



