FOLIAR ORGANS. 395 



AVitli reference to tliis point the reader is referred to 

 Mr. Bentliam's account of the morphology and homo- 

 logies of the MjjrtacecB in the * Journal of the Linnean 

 Society,' vol. x, p. 105. See also antef pp. 71, 77. 



Some doubts also exist as to the nature of the beak 

 or columella of such fruits as those of Geraniacece, 

 MalvacetVy UinbelUferce, Euphorhiacetv,, &c. The nature 

 of the organ in question may probably be different in 

 the several orders named ; at any rate the subject can- 

 not be discussed in this place, and it is mentioned here 

 because, now and then, it happens that the organ in 

 question is completely wanting, and hence affords an 

 illustration of suppression. 



CHAPTER II. 



SUPPRESSION OF FOLIAR ORGANS. 



This subject may be considered, according as the 

 separate leaves of the stem or of the flower are affected, 

 and according as either the number of members of 

 distinct whorls, or that of the whorls themselves, is 

 diminished. 



The terms aphylly, meiophylly, and meiotaxy may 

 be employed, according as the individual leaves are 

 altogether wanting, or with reference to the diminished 

 number of parts in a whorl, or a decrease in the 

 verticils. 



Aphylly. ^Entire suppression of the leaves is a rare 

 phenomenon. Under ordinary circumstances it occurs 

 in most Cactacece, in some of the succulent Euphorbias, 

 and other similar plants, where the epidermal layers of 

 the stem fulfil the functions of leaves. But even in 

 these plants leaf-like organs are present in some stage 

 or another of the plant's Hfe. 



