2 59 
Dischidia rafflesiana ( Wall .). 
clumps, in which particles of vegetable detritus and other sub- 
stances become entangled. The root-hairs lay hold, in the 
usual way, of the particles of the soil thus accumulated. 
Of greater interest, however, are those adventitious roots 
which enter the pitchers. The petiole of a pitcher usually 
bears two roots, one of which grows out on the lower convex 
side of the petiole, while the other appears on the opposite 
side, or laterally. The former is the one which usually enters 
the pitcher. The other generally remains outside, and behaves 
as an ordinary free root. In some cases, however, more than 
one root may enter a pitcher, and no doubt more than two 
may sometimes arise on its petiole. 
The question whether the pitcher-roots have the same in- 
sertion as the ordinary roots, appeared to us to be of interest, 
for this involved the further question whether the two kinds 
of root are distinct at their first orgin, or become differentiated 
later. According to Treub there is a difference of insertion, 
the ordinary roots arising from the stem, and the pitcher-roots 
from the petiole 1 . So far as the external attachment is con- 
cerned, this is the case, but the question of the actual place of 
origin of the root remained. We investigated the point care- 
fully, by means of serial sections through pitcher-bearing 
nodes. We found that there is no constant difference in the 
insertion. The tissues of all the adventitious roots examined 
are inserted on the cylinder of the stem very near the point 
where the leaf-trace bundles begin to bend out. Usually the 
insertion is rather below this point ; occasionally it is slightly 
above it, but such differences are inconstant. The pitcher- 
root grows for some distance through the parenchyma at the 
base of the petiole, before becoming free. It attains maturity 
much more slowly than an ordinary adventitious root, a fact 
which no doubt finds its explanation in the extremely slow 
maturation of the pitcher itself, as compared with that of 
a foliage-leaf. 
The roots which enter the pitchers branch repeatedly. It 
generally happens that a considerable amount of detritus of 
1 1. c, pp. 15 and 18. 
