652 



BOTANY 



PART II 



Family 2. Linaceae. Linum usitatissimum, Flax (Fig. 674), has long been 

 in cultivation. It is an annual, and bears numerous blue flowers, which last 

 only a short time, in racemose cincinni. The flower has its stamens united 

 at the base and five free styles. The stem bears numerous small narrow leaves. 

 The bast-fibres after proper 

 preparation are woven into 

 linen. The seeds from the 

 5-locular capsule yield oil. 



OFFICIAL. LINUM, 

 seeds of Linum usitatissimum. 



Family 3. Erythroxylaceae. 

 Erlhroxylon Coca is a small 

 Peruvian shrub, with entire, 

 simple leaves and axillary 

 gioups of small white flowers 

 (Fig. 675). Cocaine is obtained 

 from the leaves of this plant. 



the 



FIG. 674. Linum usitatissimum. 

 A, Flower. B, Androecinm and 

 gynaeceum. C, Capsule afUr 

 dehiscence. (A, nat. size ; B, C 

 x3.) OFFICIAL. 



FIG. 675. Erythroxylon Coca. ( nat. size.) 



Family 4. Zygophyllaceae. 



OFFICIAL. Guiacum sanctum and Guiacum ojficinale, West Indian trees with 

 opposite, paripinnate leaves. Ovary bicarpellary, bilocular. Fruit winged. 

 They yield GUIACI LIGNUM and GUIACI IIESINA. 



Family 5. Rutaceae. IMPORTANT GENEKA. Ruta graveolcns ( Fig. 676), the 

 Rue, is a somewhat shrubby plant with pinnately-divided leaves. The terminal 

 flowers of the dichasial inflorescences are pentamerous in robust examples ; all 

 the other flowers are tetramerous with a large intrastaminal disc. Dictamnus 

 Fraxinella has panicles of conspicuous, dorsiventral flowers ; the carpels are free 

 in their upper portions. The important genus Citrus ( 22 ) has peculiarly con- 

 structed flowers (Figs. 677, 678). The numerous stamens are united in bundles 



