Chap. II.] 
COURSE OF THE SAP. 
77 
which I cut off the tree in December, 1843. It 
bore fruit for the last ten of these eleven years, 
though the rest of the tree had never borne fruit 
up to the last-named year. The branch was 
alive when I cut it off. The woody part above 
the ring is, owing to its annual growth in girth¬ 
ing, double the size of the ringed part. 
It is clear that every part of the interior of 
this branch—that is, of the woody part of it— 
which existed when it was ringed in 1832 was 
in 1843 divided from the exterior bark, and 
consequently from every bud and leaf, by eleven 
annual sheaths or growths; and the upward 
sap, which nourished the bud, the leaf, the 
shoot, and the fruit in 1843, must have been 
supplied to them from the old ringed interior 
wood by lateral transmission through the eleven 
newer annual growths of wood. 
It must, however, be observed that the cone 
formed at the top of each annual growth of wood 
is not a closed cone, but an open cone. The top 
of each cone is, in fact, a crater . The pith 
passes through this crater, and the top bud is 
seated on this pith. The pith of each side-bud 
also joins the pith of the twig to which it is 
attached, as the pith of each branch which ema¬ 
nates from the stem joins the pith of the stem. 
The longitudi¬ 
nal pith-chan¬ 
nels extend 
throughout 
the tree, from 
the pith of the 
original seed¬ 
ling to the 
finest ramifica¬ 
tions of the 
roots and 
branches of the 
largest tree 
which is entirely 
alive. 
