ANNUAL, BIENNIAL, AND PERENNIAL ROOTS. 85 



ily, for example), and in nearly the whole great class to which 

 Grasses, Lilies, and Palms belong, there is no one main trunk or 

 primary root from which the rest proceed ; but several roots spring 

 forth almost simultaneously from the radicle in germination, and 

 form a cluster of fibres, of nearly equal size (Fig. 111). Such 

 plants scarcely exhibit that distinct opposition of growth in the first 

 instance, already mentioned as one characteristic of PhaBnogamous 

 vegetation. Most Phsenogamous plants likewise shoot forth secon- 

 dary roots from the stem itself, the only kind produced by Cryp- 

 togamous plants. To these we must revert, after having consid- 

 ered some diversities connected with the duration and form of 

 roots, and an important subsidiary purpose which they often sub- 

 serve. 



127. Annual Roots are those of a plant which springs from the 

 seed, flowers, and dies the same year or season. Such plants al- 

 ways have fibrous roots, composed of numerous slender branches, 

 fibres, or rootlets, proceeding laterally from the main or taproot, 

 which is very little enlarged, as in Mustard, &c. ; or else the whole 

 root divides at once into such fibrous branches, as in Barley (Fig. 

 Ill) and all annual Grasses. These multiplied rootlets are well 

 adapted for absorption from the soil, but for that alone. The food 

 which the roots of such a plant absorbs, after being digested and 

 elaborated in its leaves, is all expended in the production of new 

 leafy branches, and at length of flowers. The flowering process 

 and the maturing of the fruit exhaust the vegetable greatly (in a 

 manner hereafter to be explained), consuming all the nourishing 

 material which it contains, or storing it up in the fruit or seed for 

 its offspring ; and having no stock accumulated in the root or else- 

 where to sustain this draught, the plant perishes at the close of the 

 season, or whenever it has fully gone to seed. 



128. Biennial Roots are those of plants which do not blossom 

 until the second season, after which they perish like annuals. In 

 these the root serves as a reservoir of nourishing, assimilated mat- 

 ter (27, 79) ; its cells therefore become gorged with starch (81), 

 vegetable jelly (83), sugar (84), &c. Such thickened roots are 

 said to be fleshy , and receive different names according to the 

 shapes they assume. When the accumulation takes place in the 

 main trunk or tap-root, it becomes conical^ as in the Carrot, Fig. 

 1 12, when it tapers regularly from the base or crown to the apex ; 

 it is fusiform or spindle-shaped when it tapers upwards as well as 



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