60 



ORGANOGRAPHY. 



BOOK I. 



older botanists; Adnatitm of Richard;) which grow at the ex- 

 pense of their parent bulb, and eventually destroy it. Every 

 true bulb is, therefore, necessarily formed of imbricated scales, 

 and a solid bulb has no existence. The bulhi solidi, as 

 they have been called, of the Crocus, the Colchicum, and 

 others, are, as we shall hereafter see (see Cormus), a kind of 

 subterranean stem : they are distinct from the bulb in being, 

 not an imbricated scaly bud, but a solid fleshy stem, itself 

 emitting buds. It has been supposed that they were buds, 

 the scales of which had become consolidated ; but this hj^o- 

 thesis leads to this very inadmissible conclusion, — that as the 

 cormus or solid bulb of a Crocus is essentially the same, ex- 

 cept in size and situation, as the stem of a Palm, the stem of 

 a Palm must be a solid bulb also, which is absurd. In truth, 

 the bulb is analogous to the bud that is seated upon the cor- 

 mus, and not to the cormus itself; a bulb being an enlarged 

 subterranean bud without a stem, the cormus a subterranean 

 stem with buds on its surface. 



20 



21 



22 



Of the bulb, properly so called, there are two kinds. 



1. The tunicatcd hidb (fig. 20.), of which the outer scales are 

 thin and membranous, and cohere in the form of a distinct 

 covering, as in the onion; and, 2. the naked bulb {Bulbus 

 squamosus) (fig. 21. 22.), in which the outer scales are not 

 membranous and united, but distinct and fleshy like the inner 

 scales, as in Lilium. The outer covering of a bulb of the 

 first kind is called the tunic. 



