376 BOTANICAL GAZETTE [MAY 
leaves borne on short shoots. One of the nost noticeable things 
about the short shoots of Ginkgo is the fact that quite frequently 
they branch within the wood of the limb out of which they grow. 
In fig. 5 we have a transverse section of a branching short shoot, 
showing the two divisions entirely separate from each other, yet 
still within the wood of the branch. Fig. 6 shows this same branch- 
ing short shoot sectioned nearer the pith, with the short shoot not 
yet divided. 
SEWARD and Gowan (I.c. p. 132) say that in some instances the 
short shoot of Ginkgo may branch like the trunks of Cycas. To 
illustrate this they have reproduced a natural-sized cut (.c. pl. 9, 
fig. 42) of a branching short shoot. The branching to which they 
refer, however, takes place entirely outside of the wood of the limb, 
as is shown by their figures. 
It is of special interest in this connection to note that a new 
araucarian conifer, Woodworthia, from the Triassic of the Fossil 
Forest of Arizona, which has been examined and described by 
Professor JEFFREY’ has short shoots which likewise divide within 
the wood of the branch. This gives us convincing evidence that 
the araucarian conifers are an old group, and have possibly come 
from the same stock as the Ginkgoales. Unlike the short shoots 
of Ginkgo, those of the .araucarian conifer mentioned apparently 
never grew out into long shoots. 
Like the Ginkgoales and araucarian conifers, the older Abieti- 
neae likewise had short shoots. It would be interesting, were the 
material available, to examine the short shoots and woody branches 
of Prepinus, the probable ancestor of the Abietineae, in search 
for branching within the wood of the limb. 
Summary 
The root of Ginkgo biloba contains crystal cells and wood pat- 
enchyma distributed in rows or series which run longitudinally 
throughout the root in radial planes. 
All of these rows of cells are in contact with at least one ray- 
In some places the wood parenchyma cells can be distinguished 
5 Jerrrey, E. C., Proc. Boston Soc. Nat. Hist. 34: pls. 31, 32. 1910. 
