DISCHIDIA WITH DOUBLE PITCHERS. 383 
very similar in form to those from the inner surface of the 
pitcher of D. Rafflesiana figured by Griffith *—is important 
in this connection. The modified leaf of Dischidia, from the 
slightly concave organ of D. Collyris to the highly complex 
structures we are considering, is obviously of service in the 
water-economy of the plant, since it renders transpired water 
available for re-absorption by the roots t. That rain-water and 
tree-washings also find their way in through the orifice must 
certainly happen at least in some positions of the pitcher. In all 
cases it appears to be fixed in the same plane as the branch 
on which it is borne (PI. 9. fig. 1). The petiole being very 
short, the mouth of the funnel-shaped depression is in close 
contact with the surface of the branch. In D. pectenoides the 
orifice of a pitcher on an erect branch is directed upwards 
(cf: figs. land 3). My material does not prove this in the case of 
other species, but on morphological grounds it is in the highest 
degree probable. But the fact that the plant is a climber must 
not be overlooked. If the stem is erect, the position of the orifice 
in D. pectenoides (and probably in the other species also) will be 
such as to prevent the entrance of rain-water or washings. 
But, owing to the climbing habit of the stem, comparatively 
few of the pitchers are likely to be in such a case. A very 
slight inclination of the stem would place the orifice in such 
a position that the inflow of water would be possible. 
The small size of the orifice and the occlusion of the wider 
opening of the depression of the stem would seem to effectively 
preclude the possibility of any considerable amount of solid 
matter being washed in. Groom’s view with regard to the solid 
particles in the pitcher of D. Rafflesiana is that they are brought 
in mainly, if not entirely, by ants. This opinion is supported 
by Ridley’s observation ¢, that earth similar to that found at the 
foot of the host tree is present in the pitchers. Then we have 
Treub’s statement relating to the same species. “‘ Les ascidies 
sont devenues de véritables nids de fourmis, abritant des centaines 
Windividus et beaucoup de larves”§. Treub’s words would 
* Griffith, Trans, Linn. Soc. vol. xx. tab. 17. fig. 4. yo es 
+ Groom, Ann. Bot. vol. vii. p. 228; Karsten, Ann. Jard. Buit. xii. 
(1895) p. 167 ; Thiselton-Dyer, Aun. Bot. vol. xvi. p. 368. 
+ Groom, /. c. p. 229. 
§ Treub, Ann. Jard. Buit. vol. iii. p. 29. 
