34 



now PLANTS <iKuW. 



SicniON I v.— Different Forms or Kinds of Roots, Stems, and Leaves. 



8 1. Thj! Or^^'Jinwof Vf>;j«'tii<if)n, or tlios(» tlint havo to do with tlio lit'n iiixl ^M'owth 

 of a pliint, niooiily tlii«'(«, Itoctt , Sicin. and Lraf. And tin* plan upon wliich plants 

 iiro niadf is simple <>n<Mi;;ii. So sinipN' and so few ar<> tin; kinds of parts that ono 

 woijld hardly fxpt'ct plants to rxiiihit tin' almost endless and «'\('r pl''ii.^ins,' divor- 

 • hit y they do This diveisityis o\vin;i,'to thewonderful \ arietyof fo' ins nnder w hich, 

 without losinif theii' pi()|)er jiatnre, «'!i(h of these three (>r;,'ans inay appear. 



8j The study of the dilVei-ent shapes and apjteai'anees which thn same or^'nn 

 •takes in dilVerent plants, (»r in dilVerent parts of tlie snnie plant, (•(nnparin^ them 

 -with otu! aut)ther, is called Miir/i/iii/nifi/, and is one of tjie niosi interestin<( parts 

 of Hotaiiy. Ihit in this hook fur yonn;,' l)e<,Mnn«'rs, we lia\e (inly room to notice 

 i\u) commonest forms, and those nciv l»rietl\ nlthoni^di snUicienllv to enahlu 

 Btndents to st ndy all common plants and nndeistanil hotanical desci-iptions. 

 Those who would le.irn nioie of the structure and morpholo<.'y of plants should 

 study the Lessons in hotany. 



83. The Root is the simplest and least diversified of the three or<rans. Vet it 

 exhihits some strikinir \;ai'iatioMs. 



84. Asto()ri;>?in, theve is the priniarj/ or ori^dnal root, formeil from tli(> emhryo 

 as it jijrows from the seed, an<l the hi'unches it makes. Annuals, hiennials, and 

 many trees are ui)t to liave only such roots. ]5nt when any [jortion of their stems 

 is covered hy the soil, it nnikes .•^I'mnfjari/ roots. These are roots which spi'in«( 

 fi'om the sides of the stem. Kvery one knows that most stems nir.y he made to 

 strike I'oot when so ('o\(Med and haviui,' the darkness ;ind moisture which ai'o 

 ji^enei-idly needful foi' loots. IVrennial herhs and most shrubs strike root 

 naturally in this way undi'r pronnd. All the roots t)f plants raised from tubeis, 

 rootstoeks, and the like (74-76), .ire of this sort, jind also of plants raised from 

 slips or cuttings. In warm and damp climates there are likewise many 



85. Aerial Roots, namely, roots wiiich strike from the stem in the open aii-. In 

 Bunimer we often find them sprin<i[ing from the joints of the stalks of I ndian Corn, 



. several inches above the soil. Some of these reach the jnrround, and help to feed 

 the plant. In the famous ]ianyan-tree of India aerial roots on a larfjer scale strike 

 from the spreading branches, high up in the air, grow down to the ground and into 



I 



