1916] : HOFFSTADT—PIPER METHYSTICUM 127 
able, cells next to the cambium do not lignify and remain active. 
These are also’ scattered at irregular intervals throughout the ray. 
In section this gives the ray an irregular banded appearance (fig. 18). 
There are no growth rings. Much of the wood parenchyma 
touching the pith retains its activity at the node and divides long 
. after secondary wood has been laid down. This pushes the pri- 
mary vessels of the bundles apart at great distances, as well as the 
cells of mechanical tissue (fig. 18). 
The stem when young is packed with starch and piperin. 
Mucilage cells are scattered throughout it, and the buds especially 
are covered with mucilage. 
- Leaves 
The leaves have distinct petioles, the sheathing bases of which 
extend entirely around the stem, which becomes narrow opposite 
the point of insertion of the leaf. The leaf traces vary in number 
from 7 to 14. The bundles may be of two sizes. The lower part 
of the petiole is flattened on one side; the upper part is circular. 
The bundles form a crescent in the lower portion of the petiole 
(fig. 21), this crescent being made complete in the upper portion by 
the branching of the bundles at the points of the crescent (fig. 14). 
The secondary bundles form a more or less complete outer ring, 
are of the same type as those of the stem, and anastomose at 
any portion of the petiole. Union of the primary and secondary 
bundles, however, takes place before the traces enter the blade, 
which has 7-9 strong palmate veins, the 3 median ones running 
parallel for a while before they swing out laterally. The vernation 
of the leaf is involute. 
Branching 
Buds are borne in the bases of the sheathing petiole, the number 
varying from 1 to 3. The appearance of a single bud is often to 
one side instead of in the median position, which probably accounts 
for the appearance of branches coming from the side of the leaf. 
The buds are invested by a large amount of mucilage. The 
central bundles of the branch connect with those of the stem, and 
the peripheral ones connect with the peripheral bundles of the 
