82 



THE ROOT. 



Fig. 20, at A, shows a bulb crowded with turions, 

 some of which, a a, are in a germinating state. At B 

 is a bulb (crocus), showing tlie turions at a a, whUe at 

 b appeals one which is partially developed. 



37. Bulbous plants belong chiefly to tlie 

 great division of Monocotyledonmis plants ; 

 they produce some of the earliest flowers 

 of spring. Among them are the hyacinth, 

 the crown-imperial, the lily, and the tulip. 

 The use of the bulb being to preserve the young plant from the 

 eflect of cold, we see the bountiful agency of Providence in the 

 number of bulbous plants in cold countries. 



Small bulbs, called hulhlets^ grow uj^on the stems and branches 

 of some plants, as in the tiger-lily and tree-onion ; in the latter, 

 the bulbs, or onions, grow upon the stalks, in clusters of fom* 

 or ^YQ^ continuing to enlarge until their weight brings them 

 to the ground, where they take root ; these bulblets are trans- 

 formed buds. - 



The turnip at a, Fig. 21, has a bulbous, fleshy cau 

 dex, with fibrous roots ; the onion, b, is a tunicated, 

 the hly, c, a scaly bulb. 



Some bulbs die after the blossoming 

 of the 2:)lant ; new bulbs are formed from 

 the base or sides . of the original ones, 

 which, in their turn, produce plants. 

 This is the fact with respect to the orchis tribe ; in which 

 every year one bulb or tuber dies, and the other throws out 

 a new stem ; by this means, it changes its position, though 

 slowly, since it takes but one very short step each year. 



a. Gardeners take up bulbs as often as once in two or three years. In some 

 plants the new bulbs are formed beside the old ones ; thus they become crowded, 

 and produce inferior flowers. In many kinds, as the tulip and narcissus, the new 

 bulbs are formed under the old ones, and these become at length too deep in the 

 earth ; while the new bulbs of the crocus, gladiolus, and some other plants, grow 

 above the old ones, and on account of being too near the sm-face, are liable to be in 

 jured by frosts and drought. 



Fig. 22 shows at A, a root of Solomon's seal (Con- 

 vallaria) : a a are the young bulbs ; b marks the 

 spot from which the decayed stalk of the former 

 year has fallen ; d d are the fibers or tme root of the 

 plant. 



At B is a root of the Ixia, or Blackberry -lily ; 

 a shows tlie young bulb formed above the parent 

 one, which is withering in consequence of having im- 

 parted its vigor to its offspring. 



What was formerly called a bulbous root, is now 

 considered a bidbiferous or bulb-bearing root, smce 

 all that is truly a root is the fibrous part. 



37. Bulbous plants. — a. Reasons for taking up bulbous plants. 



