Dischidia rafflesiana (Wall). 265 
At 38 mm. the structure is very much simplified ; the 
xylem forms a continuous ring, except at one point where the 
medullary and the normal phloem are continuous. 
Woodcut C. 
From transverse section of pitcher-root 33 mm. below apparent insertion : 
px, protoxylem; x , xylem ; ph> phloem ; iph, internal phloem, x 120. 
Lastly, at 43 mm. from the base, the structure has again 
become quite normally tetrarch ; there is a small pith here, 
but no internal phloem. The branches of the root are alto- 
gether normal. 
We cannot, of course, say whether the curious anomalies 
just described are characteristic of the Burmah form of the 
species. Possibly it is merely a matter of individual variation, 
for which analogies would not be wanting. In Strychnos 
spinosa , for example, one of us observed medullary phloem in 
some roots and not in others of the same plant 1 . Jost and 
Schumann have found that medullary bundles may appear in 
the stem, as an individual peculiarity 2 , in Phctseoliis and 
Carum. 
1 Scott and Brebner, Anatomy and Histogeny of Strychnos , Annals of Botany, 
vol. iii. 1889. 
2 Jost, Bot. Zeitung, 189T, p. 485 ; Schumann, Bot. Centralblatt, Bd. 45, Heft 12, 
1891. 
