On Dischidia rafflesiana (Wall.)'. 
BY 
PERCY GROOM, M.A., F.L.S, 
Formerly Frank Smart Student of Botany , Gonville and Cams College y 
Cambridge . 
With Plate X. 
I. The Functions of the Pitchers. 
F the forty-six species which, according to Beccari 1 2 3 , 
KJ comprise the Asclepiadaceous genus Dischidia , most are 
confined to the Malayan region (including New Guinea, 
K6 Isles, Moluccas, and Philippines) : a few occur in India : 
one in tropical Australia : one is peculiar to Hong-Kong, 
and another to Formosa. All are twining epiphytes ; but, as 
far as is known, pitchers are possessed only by D. rafflesiana , 
D. iimorensis , D. complexa , and the three doubtful species 
D. merguiensis (Becc.), D. clavata (Wall.), and D. digiti- 
f or mis (Becc.). 
D. rafflesiana twines round the trunks and branches of 
trees, and it appears to prefer decaying trees 8 . Whilst some 
of its leaves are normal foliage-leaves, others are converted 
into shortly-stalked pitchers. Each pitcher is oblong ovate 
1 See also preliminary communication in Proceedings of the Royal Society, 
vol. 53. 
2 Beccari, Malesia, vol. ii. 
3 Griffiths, Notulae, vol. iv. 
[Annals of Botany, Vol. VII. No. XXVI. June, 1893.] 
