460 ABORTION 



De Candolle,^ from a consideration of Strelitzia jmicea, 

 in which the petiole alone is developed, was led to the 

 inference that in many monocotyledonous plants the 

 blade of the leaf was never developed, the portion 

 present being the sheath or stalk, unprovided with 

 limb. The correctness of this inference is shown, 

 amongst other things, by the occasional presence of a 

 leaf-blade in Strelitzia juncea itself. 



Occasionally the laminar portions of the leaf are 

 completely wanting, leaving only the main ribs, as in 

 the case of Berberisy while the adjoining figure (fig. 215) 

 represents an instance of a cabbage wherein the inner- 



FiG. 215. Inner leaves of cabbage reduced to their midribs. 



most leaves are represented by thick fleshy cylindrical 

 bodies corresponding to the midribs of the ordinary 

 leaves. There is in cultivation a variety of the cabbage 

 which constantly presents this peculiarity. 



The suppression of one or more leaflets of a com- 

 pound leaf has already been referred to at p. 396. 



Abortion of the perianth, calyx, and corolla. Illustrations 

 of partial development in these organs are not rare, 

 under ordinary circumstances, as for instance the 

 " obsolete" calyx of Umbellifers. In the cauliflower the 

 branches of the inflorescence are contracted in length, 

 while their succulence is much increased; at their 



> Org. Veget.,' i, p. 286. 



