[ 387 ] 



XXI. On the Structure of the Ascidia and Stomata of Dischidia Rafflesiana, 

 fVall. By the late William Griffith, Esq., F.L.S. &jc. Communicated 

 by R. H. Solly, Esq., F.R.S., F.L.S. 8fc. 



Read January 20th, 1846. 



L HIS curious plant occurs abundantly about Mergui, and affects old and 

 partially decayed trees. I have hence been able to examine abundance of 

 specimens loaded with Ascidia of different degrees of development. I offer 

 the observations relating to these curious appendages, as I conceive they 

 throw light on their nature, which, if analogy holds good, appears to have 

 been generally misunderstood. The commonly adopted opinion, and that 

 which Dr. Lindley advocates in his ' Outlines of the First Principles of Bo- 

 tany' and in his 'Introduction to the Natural Orders,' is, that the pitcher is a 

 modification of the petiole and the lid or operculum of the lamina. The 

 structure of Dloncea certainly seems in favour of this opinion. Mr. Brown, 

 in his " Remarks on the Structure and Affinities of Cephalotus," Lond. and 

 Edin. Phil. Mag. for Oct. 1832, says, that Ascidia in all cases are manifestly 

 formed from the leaves, but does not refer the pitcher or lamina to any par- 

 ticular part of the leaf. 



The Ascidia of this species have, as might be expected, the same arrange- 

 ment as the leaves : they are opposite and shortly pedicellate. They are how- 

 ever crowded together, while the leaves are distant. In shape they are oblong- 

 ovate, somewhat compressed, with a few elevations and depressions, which \^f 

 correspond to those formed in the leaves by the nervures. They are open at 

 the base, the margins being rounded off owing to their being inflected into 

 the pitcher in the shape of a linguiform process. Immediately below the base 

 they are slightly constricted. The opening is invariably directed upwards. 

 Their colour externally is that of the leaves, — a dingy yellowish green, often 



■i. 



