24: GENERAL FACTS RELATING TO ^VjEGETABLES. 



to form a genus, and genera together to form an order, and orders together to form 

 a class, we then proceed by synthesis, "wliich means putting together. 



23. General Facts relating to VegetaUes. — ^Tlie solid part of 

 plants, or tissue^ is composed chiefly of fibers and meinhranes^ 

 which form tiibes and cells for conveying and containing fluids. 

 AVhen the fibrous portion predominates, the plant becomes 

 tough and woody ; and when the cellular structure prevails, the 

 product is tender and succulent. The various vegetable tissues 

 will be considered more fully hereafter. Plants ai^ furnished 

 with 23ores (stomatd)^ by which they imbibe nourishment from 

 surrounding bodies. The part which fixes the plant in the 

 earth and absorbs from it the juices necessary to vegetation, is 

 the root ; this organ is never wholly wanting. The sterti^ or 

 ascending axis, does not always rise ; it sometimes creeps upon 

 the earth, or remains concealed in its bosom ; but, generally, 

 the stem ascends either by its own strength, or, as in the case 

 of vines, by supporting itself uj)on some other body. The 

 divisions of the stem are its hranclies ; the divisions of 

 the branches are hranclilets^ or houglis. When the vegetable 

 has no stem, the leaves, flower, and fruit grow from the tops 

 of the root ; but when the stem exists, that, or its branches, 

 bear them. Herbs in which cellular tissue abounds, have soft, 

 watery stems, of short duration, which bear flowers once, and 

 then die. Trees and sliriibs^ being mostly formed of fibrous 

 tissue^ have solid and woody stems ; they live and bear flowers 

 many years. Small bodies of a round or conical form, consist- 

 ing of tjiin scales, lying closely compacted together, appear 

 every year upon the stems, the boughs, and the branches of 

 trees. They contain the germs of the productions of the fol 

 lowing years, and secure then from the severity of the seasons. 

 These germs, and the scales which cover them, are called bads. 

 The buds of the trees and shrubs of equinoctial countries, have 

 few scales, as they are less needed for protection against in- 

 clemencies of weather. Leaves like flowers proceed from 

 buds ; they are the lungs of vegetables ; they absorb water and 

 carbonic acid from the atmosphere, decompose them by the 

 action of rays of light, and exhale or give out oxygen gas. 

 They are tough and dry, soft and watery, in proj)ortion as the 

 fibrous or cellular tissue prevails. 



Yegetables, like animals, produce others of their kind, and 

 thus 2:»erpetuate the works of creation. The organs essential to 

 the perfection of plants, are the stamens and pistils. The pres- 

 ence of a stamen and pistil constitutes what is called a perfect 

 flower ; but, in general, these organs are surrounded with an 



23. Tissue— Stem— Branches— Bonghg—Herba— Trees aad Shrubs— Buds— Leaves— Essential o^ 

 eana. 



