132 ELEMENTARY BOTANY. 



reddish-brown. The constituents of the seeds are cocoa-butter 

 thirty-four to fifty-six per cent; the alkaloid theobromine (which 

 imparts the bitter taste), sugar, cellulose, starch, and albu- 

 minoids. The seeds are used in the manufacture of butter of 

 cocoa (used in perfumery) and of chocolate and cocoa. The 

 seeds are roasted, then ground into a paste; to this are added 

 vanilla, sugar, etc., forming chocolate, or without these vari- 

 ous ingredients it is cocoa. The Vanilla plant ( Vanilla plani- 

 folia) is a member of the Orchid family. It is an epiphyte, 

 growing on trees in tropical America, now cultivated in 

 India, Eiist Indies, and elsewhere. It has thtfck, laurel-like 

 leaves and inconspicuous flowers. The fruit is a fleshy cap- 

 sule five or ten inches long ; it is gathered before maturity, 

 wrapped in wool, heated, and then exposed. This process is 

 repeated till the fruit is dry ; the odor and the brown color in 

 the meantime become fully developed. Upon analysis the fol- 

 lowing constituents have been found : tannic acid, resin, fat, 

 wax, gum, sugar, and an aromatic substance, namely, vanillin. 

 The flowers of the Vanilla plant when cultivated out of its 

 native country must be artificially pollinated. It is propa- 

 gated by attaching scions to trees, which produce fruit after 

 three years, and continue to bear thirty to forty years. Its 

 culture is carried on in connection with the culture of the 

 Chocolate tree, on which the Vanilla plant grows. 



25. The various plants furnishing important and indispen- 

 sable foods and medicines are extremely numerous. The 

 Cereals belong to the Grass family (Graminese'). As furnishing 

 food for man and animals and other useful products, this large 

 family of plants ranks first in importance. The Palm family 

 ranks second for the importance of its products. In the coun- 

 tries in which the various species grow, the fruits (and the 

 other products) are extensively used. Many kinds are ex- 

 ported, as dates, cocoanuts, etc. A large number of our com- 

 monest fruits are furnished l^y the Rose family ; many also 

 are obtained from the Bean family, the Mustard family, the 

 Parsley family, the Nightshade family, the Orange family, the 

 Banana family, and many others. 



