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VII. On some Points/ in the Morphology and Anatomy of the Xymphncacejc. By D. T. 

 Gwynne-Vauohan, B.A. Cantab. {Communicated by D. 11. Scott, F.R.S., F.Z.S., 

 Hon. Keeper of the Jodrell Laboratory ^ Royal Gardens, Keio,) 



(Plates XXI. & XXII.) ,; 



Read 18th February, 1897. 



Morphology of the Leaf 



oOME time ago the rliizomc of a mature plant of Victoria regia and also a number 

 of young seedlings of the same which had been grown in the Royal Gardens, Kew, were 

 placed in my hands ; and I spent some time under the direction of Dr. Scott, for whose 

 valuable advice and supervision throughout X have every reason to be grateful, in 

 examining the material thus placed at my disposal. In the course of this examination 

 various points of such interest came into view as to lead to the investigation of other 

 plants of the same order for the sake of comparison. Some of the results obtained 

 thereby I have ventured to detail in this paper. 



In dissecting away the growing-point of the mature rhizome some of the earliest 

 stages of the adult leaves were disclosed, and since I have not met with any figures 

 of the well-known leaf in its young state, three of them are represented on an enlarged 

 scale in PL XXI. figs. 1, 2, & 3. 



The smallest leaf figured is about 1'5 mm. long ; and here it may be seen that the 

 rudimentary lamina stands erect and broadly based on a short, stout support, the future 

 petiole, the extension of the lamina below the point of insertion being much less than the 

 extension above it. So the petiole is inserted excentrically, and the general outline of 

 the lamina is ovate and not orbicular. The sides of the lamina are raised up like those 

 of a bowl, the edges being rounded off owing to the fact that they are slightly curled 

 inwards, although the involute prefoliation which is a characteristic of the young leaf in 

 its later stages is not nearly so prominent in the earlier ones. 



The apex tapers to a blunt point slightly incurved, and differing but little, if at all, in 

 texture or appearance from the rest of the leaf — quite otherwise than what might be 

 expected from the case of Luryale ferox. Judging from a plate of that plant given in 

 the ' Flore des Serres et des Jardins de I'Europe,' illustrating a description written l)y 

 Planchon, the general appearance of an early stage of an adult leaf is closely similar 

 to that described for Victoria regia ; on the other hand, the apex takes the form ot a 

 broad terminal lobe folded over on to the ventral surface like a hood, being almost free 

 from prickles, and not partaking in the involution of the rest of the leaf. 



In view of the suggestion put forward by Baillon with regard to the differentiation of 

 the pitchers of Sarracenia, Nepenthes, &c., that they were derived by an extreme 



SECOND SEEIES. — BOTANY, VOL. V. 2 T 



