388 BULLETIN OF THE BUSSEY INSTITUTION. 
On multiplying these figures by the conventional factor 1.84,* the results 
may be stated in terms of pentosans, as follows : — 
The tree felled in Contained pentosans, per cent, in the 
Inner Wood. Outer Wood. Bark. 
BLOG eo reece tee Saas 36.10 30.82 
SULLY 5 ebmita estos tx, te eh te ee 
: 34.67 21.07 
ih Or Ah rata Tod BRS, coat ‘ 
October Pas) 29.80 29.97 22.67 
See, further, page 395, for the quantities of pentosans detected in other 
kinds of woods. 
It will be noticed that the proportion of pentosans in birch 
wood is somewhat larger in May than in October, presumably 
because other matters were stored in the tree in October and ex- 
hausted from the tree in May, though it is to be said that the 
method of estimating furfurol by means of phenylhydrazin acetate 
is hardly sufficiently accurate, as an analytical process, to permit 
of too much emphasis being Jaid on the observations here re- 
corded. It is to be remembered also that a small proportion of 
the furfurol obtained may, perhaps, have come from albuminoids 
or from hexoses in the wood. 
As a matter of course fatty and nitrogenous matters in the tree 
may serve as well as starch for feeding new buds and leaves, and 
it is true also that the twigs and young branches of a tree will 
naturally be richer in starch than the older wood of the trunk or 
stem. It is not impossible that these matters acting in conjunc- 
tidn with the comparatively small quantities of starch found in 
the older wood and bark, may be sufficient to provide the tree each 
year with its new suit of leaves, even as in the familiar instance 
of the taking of carbon from the air by green leaves mere traces 
of matter are seen to be competent to produce effects of enormous 
magnitude. Still it would seem to be more probable that, beside 
starch, oil, and albuminoids, there are contained in wood and bark 
other chemical substances, presumably hexosans, which may take 
part in the act of developing new foliage. 
From the analogy of the hard seeds of the date and other palm- 
trees, which contain a much smaller proportion of pentosans than 
wood contains, but which are known to be rich in hexosans and 
to be fully competent to supply food to the young plant at the 
* Wiley’s Agricultural Analysis, 3. 587. 
+ De Chalmot, American Chemical Journal. 1893, 15. 23, 277. Tollens, 
Kurzes Handbuch der Kohlenhydrate, Breslau. 1895, 2, 52, 73, 163. 
i © yee ae 
