390 Mr. Grirrits on Dischidia Rafflesiana. 
of the pitcher and both surfaces of the leaves they are greenish, from a deposit 
of minute green corpuscles (Tas. XVII. figs. 4 & 6). The space between the 
Stoma and the inner margin of the innermost circle is invariably uncoloured ; 
any imperfection, when it does exist, is confined to the Stoma, the surround- 
ing circular tissue being in such instances perfect. The fact of the existence 
of Stomata in the inside of these Ascidia, where there can be but a compara 
tively small ingress of light and air, is curious enough, particularly when 
-coupled with the deep coloration of the tissue. on which they are developed ; 
and one is naturally led to ask, Can they have the same functions with those | 
of ordinary foliaceous structure? May not the functions of those in which 
the Stoma is opake be glandular? | 
November 7, 1834. 
EXPLANATION OF TAB. XVII. 
Fig. 1. A portion of the stem of Dischidia Rafflesiana, Wall., bearing a pair of leaves and a 
pitcher; the latter longitudinally divided :—of the natural size. 
Fig. 2. A pair of young pitchers; one well-developed, the other partly abortive. 
Fig. 3. Stoma, from the upper surface of the leaf, which corresponds to the inner surface of 
. the pitcher. : 
Fig. 4. The same, with the bourrelet removed. 
Fig.5. Abortive stoma from the surface of the leaf corresponding to the outside ofthe - 
[v pitcher. 
Fig. 6. The same, with the bowrrelet removed. 
All the figures of the Stomata are viewed as transparent objects, and with triplets of - j 
ig ands. of an inch focus. _ 
