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"The colour of the inflected portion internally is ranch lighter than 

 that of the corresponding surface of the leaf: its outer surface is of a 

 light purplish brown. They appear at no period to contain fluids, but 

 invariably contain one or more branched roots, which, taking their 

 origin from various parts of the petiole, pass down through the opening. 

 These roots are always more succulent and of a lighter colour than 

 those formed in any other part. Their structure is precisely that of the 

 limb of the leaves ; the only difference being in form and in the colour 

 of the inner surface, which corresponds to the concave of the leaves.* 

 This structure presents nothing peculiar with the exception of the sto- 

 mata. The proofs 1 have to give of their being modified laminae are : — 



" 1. Their similarity in texture and internal structure, and that of 

 the stomata with those of the limb of the leaves. 



" 2. There is a constant and appreciable though slight tendency in 

 the limb of the leaves to assume an involute form, their margins and 

 apex being always, and especially in old leaves, more or less incurved. 



" 8. The occurrence of an imperfectly transformed pitcher, in which 

 the body of the pitcher is clearly referrible to the limb of the leaf. 

 The petiole has retained its usual form. This specimen resembled 

 closely the bottom of a perfect pitcher, being, however, much less 

 compressed : it was completely open at the top, no constriction hav- 

 ing taken place. The margins and apex were slightly incurred : 

 there was a slight tendency towards coloration, but only towards the 

 fundus. 



" 4. In this family at least it is more natural to refer the ascidia to 

 the limb from the general construction of their petioles. 



" If we can extend the analogy drawn from the structure of the 

 ascidia of this plant to the other cases of their formation, in Nepen- 

 thes, Cephalotus and Sarracenia, in which the development is much 

 more perfect, we shall have a petiole of ordinary form and a curiously 

 modified limb, the lamina being an appendage of the limb. I consider 

 the inflected portion of the pitchers of Dischidia as analogous to the 

 movable opercula of the more perfect examples cited above, although in 

 this it is continuous with the body of the pitcher. Mr. Brown however 

 says {loc. cit.), that the ascidia of Dischidia have no larainse. I may 

 add, that petioles are much less liable to modifications than laminae. 



" * The leaves are smooth and somewhat concave on one surface, convex and 

 rugose on the other ; but the whole growth is so straggling, that it is difficult to say 

 which is the upper and which the under surface. I think that the inner surface of 

 the pitcher corresponds to the upper of the leaves, that being the smooth concave 

 surface." 



