OF TENDRILS, ; 287 
The whole subject is, however, worthy of investigation. 
Stellate should be particularly examined with this view, but 
itis no argument against my idea that they are ever con- 
verted into leaves, for such is the case in a greater or less 
degree with the inner scales of those which have imbricated 
bud-scales. 
TENDRILS. 
These organs are referred by Lindley to petioles, and by 
Link to branches. There is however, no doubt, that the for- 
mer opinion is much nearer the truth than the latter. But 
instead of confining the metamorphosis to the petioles, it is 
more consonant to the nature of these organs to attribute it 
to the leaves entirely. The proof of this exists in those Cu- 
curbitace in which the tendrils are branched; the branches 
occasionally corresponding to the divisions of the petiole into 
veins in the leaves. The only objection to this view in Cucur- 
bitacee is, that the leaves are not strictly opposite to the 
cirrhi, but this may perhaps be explained by a change in di- 
rection of the continuation of the axis. The greatest division 
of cirrhi takes place in some tribes (Cissi) with compound 
leaves : and I see no reason for supposing them to be in this 
order modifications of the peduncle. The idea of St, Hilaire 
regarding these organs in Cucurbitacez is not borne out by 
a single fact. In certain species of Smilax the lateral leaves 
are cirrhiform, the terminal one alone arriving at its full 
development. An additional instance of a cirrhus terminating 
a leaf, that is of the midrib becoming elongated, exists in 
Flagellaria indica. An instance of the petiole being narrowed 
into a cirrhus, and again expanding, exists in Nepenthes. 
The idea that the tendrils are branches, and opposite in 
some cases to the leaves, may be explained by supposing the 
continuation of the stem or axis to be from the axis of the 
developed leaf, and such a case may, and does often exist, but 
it is quite sufficient to look at them in the pea, etc. to be at 
once convinced that they are modifications of leaves. ; 
