INTRODUCTION. 13 



the active fibres are renewed and shed annually. 

 Some are thick and of considerable length, as 

 narcissus and hyacinth ; others are extremely 

 attenuated. 



It has been a question among florists, how far 

 the flower and leaves of a plant are nourished by 

 its bulb or tuber, that is, whether they yield 

 nourishment as well as protection. The outer 

 coverings of narcissus, hyacinths, bulbous iris, 

 &c. appear to be only the remains of former or 

 unexpanded leaves, which continue to act as a 

 covering, as before observed, till the slough of 

 the radical plate from which they sprung falls 

 off. The interior of these bulbs is occupied by 

 the flower, stem, and leaves, in the winter ; all 

 of which are expanded in the spring and summer. 

 As these go forth, their former space is gradually 

 filled by the next year's bulb. Now, all these 

 expanding parts being previously formed, their 

 developement cannot be said to depend entirely 

 on themselves, but on some other part of the 

 system which can assist their expansion, namely, 

 the roots, which imbibe elemental food. Can 



