CALYX-TUHE. 481 



the receptacle of a ring or tube under them, as in the 

 stamens of Leguminosiii ; yet, says Mr. Bentham, no 

 one would propose to describe the staminal tube of 

 monadelplious Lcgiiminosce as part of the receptacle 

 and not of the stamens. Perhaps not, fot descriptive 

 purposes, but morphologically it would not be easy to 

 separate such a tube from the receptacle. The principal 

 kinds of malformation which have a bearing on this 

 subject are mentioned at pp. 77 81 and 247, from 

 which it may be seen that the evidence furnished by 

 teratology is conflicting. It would seem, indeed, that 

 while in some families of plants there may be a real 

 calyx-tube, in others the tubular portion is a sheath- 

 like prolongation of the axis. In Primula or Pedicu- 

 laris, where the venation is clearly laminar, the tubular 

 portion is distinctly calycine. In other cases the so- 

 called calyx-tube seems as certainly to be an expansion 

 of the receptacle, as in Bosacece, Myrtacece^ Melasto- 

 TncLcefB, Pas^iflora,^ &c. 



Where the petals and stamens are described as being 

 inserted into the throat of the calyx, or are perigynous, 

 it may be assumed as a general rule, subject to but few 

 exceptions, that the so-called calyx-tube is really a por- 

 tion of the receptacle.^ After all, this is very much a 

 question of words, and for the following reasons, very 

 often the base of the calyx does evidently form a tube, 

 and no one can say where the calyx ends and the 

 receptacle begins. Again, many leaves are known to 

 originate in the form of a ring-like protrusion from the 

 axis, and from this primary ring originate secondary 

 developments. Thus the asserted difference between 

 a leaf, with such a history of development, and an axial 

 structure becomes obliterated. From this point of view, 

 peltate leaves like those of Tropoeolum or Nelunibiiim 

 become very significant. In both the leaf-stalk is 

 cylindrical and traversed, as in the case of all cj'lin- 



' In Passifiora the organogeny of the flower clearly shows the truth 

 of this assertion, as was inde^ shown by Payer and Schleiden. 

 ' See Payer, ' Organ. Veget.' 



-31 



