FUNCTIONS OF BULBS, CORMS, ETC. 



leaves) are soft and herb-like in texture, and there is nothing woody 

 about them as seen in trees and shrubs, and their underground 

 organs may live for several years. The possible exceptions are 

 Beschorneria and Testudinaria, which have swollen woody bases. 

 It will prevent misunderstanding to state that perennial herbaceous 

 plants^ may be divided into various groups. Thus they may be 

 either (1) hardy, (2) half-hardy, or (3) tender — each group requiring 

 different culture, treatment, and temperature. Again, herbaceous 

 perennials may be either (1) deciduous, in which the floral stems 

 and leaves die down every year, and the root-stock has a period of 

 rest (as in Tulips, Daffodils, Hyacinths, Begonias, Paeonies, Solomon's 

 Seal, Arum Lilies, etc., etc.) ; or they may be (2) evergreen, in which 

 the plants are always in a state of growth, and have foliage at all 

 periods of the year (as with Pancratiums, many Crinums, some 

 Irises, etc.). 



It may be well to bear these distinctions in mind, as there is a 

 popular and consequently erroneous impression that all herbaceous 

 plants are hardy and die down to the ground each year. 



We may now consider why certain plants are provided with 

 bulbs, corms, tubers, or rhizomes. We have already seen that the 

 normal stem has been reduced in the case of the bulb to a very 

 small compass — a mere disc-like mass with the thick fleshy leaves 

 densely arranged upon it. If a bulb of a Tulip, Hyacinth, or Daffodil 

 is cut through vertically and compared with a ripened bud of a 

 Horse-chestnut, Lilac, or Ash, it will be seen that they are all very 

 similar in structure. In the centre will be found the miniature 

 flower - stem with its incipient blossoms packed away into the 

 smallest possible compass, and carefully protected with the envelop- 

 ing scales — really leaves specially modified for this particular 

 purpose. In the case of bulbs, however, which are detached and 

 independent bodies (unlike the buds of the Horse-chestnut, etc.), the 

 scale leaves are not only protectors ; they are also storehouses in 

 which food and nourishment have been stored away by the green 

 aerial leaves before these withered and died. The corm or solid 

 " bulb," and also the tuber and rhizome utilise the stem, and not 

 modified leaves, in which to store up their nourishment in the same 

 way for the development of future growth. Consequently, season 

 after season this work is going on, and as the older storehouses 



* "Annuals "and '"Biennials" of all kinds are necessarily herbaceous in 

 character, but arc not considered in this volume, as they have neitlier bulbs, 

 corms, tubers, nor rhizomes. 



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