110 



OEGANOGEAPHY. 



in their axils new bulbs {fig. 214, c) ; these are called by- 

 gardeners cloves, and their presence is an additional proof of the 

 analogy of a bulb to a branch or bud. 



Fig. 215. Vertical section of a scaly bulb of the Lily. Fi^. 216. Scaly bulb 



of the Lily a. Shortened axis. 6. Roots. d. Flowering stem. 

 i c. Scales. The letters refer to the same parts In both flgures. 



J There are two kinds of bulbs commonly distinguished by bo- 

 tanists, namely the tunicatcd {fig. 217), and the scaly {fig. 216). 

 The tunicated bulb is well seen in the Onion {fig. 217) and 

 Squill. In this kind of bulb the inner scales, which are thick 



Fig. 217. 



Fig. 218. 



Fig. 211. Tunicated bulb of the Onion. Fig. 218. Stem of a species of 



iiily {Lilinm bulbiferum) bearing bulbils or bulblets, a, a, in the axils 

 of its leaves. 



and fleshy and enclose each other in a concentric manner, are 

 covered externally by thin and membranous ones, which form a 



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