270 VEGETABLE ORGANOGRAPHY. 



the prolongation of the peduncles ; this supposes the 

 total or partial abortion of the flowers which they ought 

 to bear. Thus, for example, it is easy to satisfy oneself 

 that the tendrils of the Vine and all the Ampelideae are 

 peduncles ; in fact, we always see that they are opposite 

 the leaves as the bunches are, and it is not rare to find 

 some which are half furnished with flowers and half with 

 tendrils. The little bundles which are found at the upper 

 part of the Vine, frequently present states intermediate 

 between absolutely fertile bunches and those which, by 

 the abortion of the flowers, are changed into tendrils. 

 Analogous facts tend to prove that the tendrils of Pas- 

 sion-flowers are likewise only abortive peduncles, for 

 they occupy their places in the axils of leaves ; and in 

 some species, as in Passlflora clrrhiflora^ the peduncle, 

 which is branched, is partly changed into tendrils and 

 partly furnished with flowers. The pedicels at the 

 base of the scapes of Cardiospermum, and of some 

 other Sapindaceae, are almost always transformed into 

 tendrils. In a species of Smilax, several of the axillary 

 peduncles are transformed either usually or accidentally 

 into tendrils, which must not be confounded with those 

 which spring from the petiole. 



Bracts and sepals so resemble leaves in their nature, 

 that it is difficult to believe that they are not capable of 

 being transformed into tendrils ; the examples, however, 

 of this transformation are rare and doubtful. The floral 

 leaves of Fritillaria verticillata change into tendrils 

 very analogous to those of Gloriosa superba; the sepals 

 of Calytrix are prolonged into a very slender filament, 

 which seems to be the rudiment of a tendril analogous 

 in form to that of Orobus. The awns of the glumes of 

 the Gramineae also appear to be an analogous degenera- 

 tion; according to Rceper, the glume represents the 

 sheath, and the awn is the abortive limb. They 



