OALYX-TUBE. 481 
the receptacle of a ring or tube under them, as in the 
stamens of Leguminose ; yet, says Mr. Bentham, no 
one would propose to describe the staminal tube of 
monadelphous Leguminose as part of the receptacle 
and not of the stamens. Perhaps not, for 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 O47, 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 Rosacew, Myrtacece, Melasto- 
mace, Passiflora,' &e. 
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-lixe 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 Tropwolum or Nelumbium 
become very significant. In both the leaf-stalk is 
cylindrical and tr aversed, as in the case of all cylin- 
‘ In Passiflora the organogeny of the flower clearly shows the truth 
of this assertion, as was indeed shown by Payer and Schleiden. 
2 See Payer, ‘Organ. Veget.’ 
[3 ) 
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