STRUCTURE.] 



BULBS CORMS. 



175 



in the axils of its scales new bulbs, or what gardeners call 

 cloves, (Nucleus and Adnascens of the older botanists ; Adna- 

 tum of Richard ;) which grow at the expense of their parent 

 bulb, and eventually destroy it. In this respect it behaves 

 exactly like a leaf-bud after it has lengthened into a branch. 

 Every true bulb is, therefore, necessarily formed of imbricated 

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

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

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

 subterranean stem : they are distinct from the bulb in consist- 

 ing not of imbricated scales, but of a solid fleshy mass, itself 

 emitting buds. It has been supposed, indeed, that corms 

 might be buds, the scales of which had become consolidated ; 

 but the hypothesis leads to this inadmissible conclusion, 

 that as the corm or solid bulb of a Crocus is essentially the 

 same, except in size and situation, as the stem of a Palm, the 

 stem of a Palm mast be a bulb also; which is absurd. In 

 truth, the bulb is analogous to the bud that is seated upon 

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

 succulent bud without a stem, the corm a subterranean stem 

 with buds on its surface. 



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



1. The tunicated bulb (fig. 21), 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- 22. 23.), in which the outer scales are 

 not membranous and united, but distinct and fleshy like the 



