ANGIOSPERMiE, DICOTTLEÜONES 765 



Rubiaceae, Coffeacece, Sambucaccae, and of the genus Linncea, contains one seed, 

 in most Caprifoliacese, as in the genus Lonicera, several, and in the Cinchonaceae, 

 many seeds. The seeds of Cinchonaceae are winged (see p. 423, fig. 318 "). 



The Caprifoliales are distributed over all parts of the earth. The Cofieaceas and 

 Cinchonaceai are chiefly tropical plants, whilst the Rubiacete, Sambucacece, and 

 Caprifoliaceas belong principally to the North Temperate Zone. The Cinchona is 

 found wild only in the Cordilleras in South America (from 10° north lat. to 22° 

 south lat.). Tropical Africa is supposed to be the original home of the Cofteo-tree 

 {Coffea Arabica). Linncea borealis, a plant named after the Swedish botanist, 

 Linnaeus, is scattered over the Alps, in the low-lying part of Germany adjoining 

 the Baltic, and in Scandinavia. Several species of the genus Galium, of the family 

 Rubiacea3, belong to the flora of the extreme North and of high mountains. Fo?sil 

 remains have been preserved in the deposits of the Mesozoic and Tertiary Periods. 

 The nimiber of extant species discovered up to the present time is about 4800. 



Alliance XLVII. — Asterales. 



Families: Valerianacece, DipsacecB, Calyceracece, Brunoniacece, Compositce. 



Annual and perennial herbs, shrubs, and trees. Foliage-leaves extremely various 

 in form but always destitute of stipules. Inflorescence a cyme or a capitulum. 

 Flowers actinomorphic and zygomorphic, hermaphrodite, pseudo- hermaphrodite, 

 monoecious, and dioecious. Floral-leaves diflerentiated into calyx and corolla. 

 Calyx of 2-5 sepals; the limb, which crowns the inferior ovary, is in the form of 

 a pappus, bristles, scales, teeth, callosities, or membranous borders, and is destitute 

 of chlorophyll. The corolla is composed of 4-5 connate petals. The gynaeceum 

 consists of 2-3 connate carpels. The ovary is inferior and contains only one devel- 

 oped loculus with a single ovule in it (see p. 73, fig. 207 ^). The andrceciuni consists 

 of 1-5 stamens. The filiform filaments are adnate at the base to the corolla-tube. 

 The fruit is a unilocular, one-seeded achene. 



The plants belonging to this alHance exhibit for the most part herbaceous growth, 

 but some Compositse are shrubby (e.g. Baccharis), and some arboreal (e.g. Vanillos- 

 mopsis, Lychnophora). Several Valerianaceae and Compositae, e.g. the Dahlia 

 and Jerusalem Artichoke (Dahlia variabilis and Helianthv^ tuberosus), are distin- 

 guished by underground tuberous structures. The Inflorescence in Valerianaceae is a 

 much-branched cyme (see p. 305, fig. 289 '). In Dipsaceae also the arrangement of 

 the flowers is cymose, but the cymes are usually grouped together in capitula (see 

 p. 121, fig. 225^). In some genera, such as Morina, they are arranged in opposite 

 fascicles in the same manner as in Labiatae. The flowers of Compositae are situated 

 at the extremity of a thickened axis which is conical, hemispherical, or flat, and 

 compressed, as the case may be; they are spirally arranged and are grouped to- 

 gether in capitula (see p. 242). In many cases they spring from the axils of scales 

 ("paleae"), or else their place of origin is surrounded by bristles. Not infrequently 

 they spring from little depressions, and then the axis is seen to be pitted when the 



