644 



BOTANY 



PART II 



Anncria and Statice are common plants of salt marshes and salt-steppes in all parts 

 of the world. 



B. Tetracyclicae 



Fki. 674.— Oleaceae. Floral 

 diagram (Syringa). 



Order 4. Contortae 



Plants with decussate, usually simple leaves and actinomorphic 

 flowers, the corolla of which is often contorted in the bud. Stamens 

 epipetalous. Ovary of two carpels, superior. 



Family 1. Oleaeeae. — Shrubs or trees without stipules. Flowers 

 tetramerous, but with only two stamens. K 4, 

 0(4), A 2, G(2). Oorolla with valvular or 

 imbricate aestivation. Ovary bilocular ; two 

 ovules in each loculus (Fig. 674). 



Distributed in all regions and zones ; especially in 

 South and East Asia. 



Important Genera. — Olea euro2)ea, the Olive {^~), 

 a native of the MediteiTanean region and of Western 

 Asia, wliere also it is cultivated. It is a tree witli a 

 poorly developed crown of slender pendulous branches 

 bearing lanceolate, simple, entire leaves, which are 

 dark green above, greyish green beneath. The flowers are borne in axillary 

 racemes or panicles. The fruit is a drupe, both the succulent exocarp and 

 the endosperm of which contain a fatty oil (Figs. 676-678). Ligustrum vulgarc, 

 the Privet. Jasminum and Syrint/a (Fig. 674) are grown as flowering shrubs. 

 Fraxinus, the Ash, lias imparipinnate leaves ; F. excelsior has apetalous, anemo- 

 philous flowers, which appear before the leaves. F. ornus, the Flowering Ash, has 

 a double perianth and is entomophilous ; it is polygamous, having hermaphrodite 

 flowers as well as female flowers with black sterile anthers ; the corolla is divided 

 to the base (Fig. 675). 



Official. — Olea europca yields oleum olivae. 



Family 2. Loganiaceae. — Herbs, shrubs, or trees with stipulate leaves. Flowers 

 pentamerous with two carpels. Tropical. Species of Strychnos, which are trees or 

 lianes climbing by means of hook-tendrils, yield the arrow poison as well as the 

 well-known Curare of South America, and that used by the Malays. 



OvFWiAL. —StrycJnios nux voviica is a small tree or shrub of Southern Asia, the 

 fruits of M'hich ai-e berries with a firm rind ; in the succulent pulp a small number 

 of erect, circular, disc-shaped seeds are embedded (Fig. 679). It yields nux 

 VOMICA and stuychnina. Gelsemii radix is obtained from Gclscinmm nitidum, 

 Mhich is a native of North America. 



Family 3. Gentianaeeae. — Herbs, with exstipulate leaves. 

 Corolla contorted in the bud (Fig. 680). The two carpels are united 

 to form a unilocular ovary. Ovules numerous. 



Generally distributed. 



British Genera. — Gentiana (^^) is a genus with numerous species. Plants of 

 larger or smaller size, especially abundant in the Alps. Flowers brightly coloured. 

 This genus affords one of the l)est examples of seasonal dimorphism, i.e. the split- 



