CHAPTER XII 



BULBS IN POTS, BOWLS, AND GLASSES 



A TRUE bulb is a thickened root stock provided with a 

 central stem and surrounded by fleshy leaves, as in the 

 hyacinths and lilies. Its nature can be seen by cutting off 

 the growing point of the stem. When this is done the buds 

 in the axils of the leaves lower down start to grow and pro- 

 duce numerous small side-shoots or bulbils, which, if taken 

 off and planted separately, will flower as soon as they are 

 large enough. This is the way in which any particular variety 

 of hyacinth is propagated. 



If the thickened root-stock is solid — that is, destitute of 

 the surrounding leaves — it is called a corm when it is upright 

 and more or less symmetrical, as in the crocus, and a tuber 

 when it departs from that shape and is provided with several 

 buds or eyes, as in the begonia or dahlia,- instead of only one. 

 In popular phraseology, however, the word bulb is often 

 applied to all three forms. A rhizome, it may be mentioned 

 here, is merely an elongated tuber which creeps along the 

 surface of the ground. For instance, among ferns the 

 Davallias are rhizomatous, and among other plants many 

 species of iris. 



The thickening of the root-stock in bulbous plants is 

 due to the fact that they earn more food than they are able 

 to spend in the same time, their savings being stored up at 

 the base of their stems. There is, of course, no purpose in 

 their economy ; they are merely the passive subjects of their 

 environment. They grow naturally in seasons of plenty, 

 when the temperature is most favourable to them. Towards 

 the end of those seasons, as the result of the gradual change 



