332 BOTANICAL GAZETTE * [APRIL 
consisted of a segment of a root several inches in length and con- 
taining about 25 annual rings. On one side a severe wound had 
been partially healed over. A photograph of a transverse section 
taken some distance above the wound is presented in fig. 1. Even 
at this low magnification, characteristic tangential series of trau- 
matic resin canals may be observed in the 5th, 6th, gth, and rath 
annual rings. Therefore, the root must have been wounded at 
least four times. The repeated wounding had apparently sapped 
its vitality, for the later-formed annual rings were very narrow and 
infested with fungus filaments. 
A more magnified view of one of the series of canals is shown 
in fig. 2. The arrangement is seen to be typically traumatic. In 
other respects the wood is of the normal A dies type. 
A radial longitudinal section, taken at some distance from the 
outermost wound, is photographed at rather low magnification in 
fig. 3. Near the left of the figure the septated element and its neigh- 
bor on the right, which is also septated beyond the limits of the figure, 
form part of the traumatic series between the canals. Immediately 
on their right two ray tracheids are to be seen on the upper margin 
of the ray. The magnification is not sufficient to show the char- 
acter of their pits except that they are smaller than those of 
neighboring wood tracheids. 
The character of the pits on a similar element may be distin- 
guished, however, in fig. 4, which is a photograph at a higher 
magnification of another section. Two of the pits in section on 
the extreme left are clearly bordered on the upper side and simple 
on the parenchyma side. The others, though not so clear, are 
likewise unilaterally bordered; therefore the long low element is 
a ray tracheid. 
That interspersed as well as marginal tracheids are present is 
shown in fig. 5. The two pits on the conspicuous vertical end wall 
are distinctly bordered, as are those on the horizontal walls of the 
same cells. Therefore, these cells are ray tracheids occurring 
between the parenchymatous cells of the ray which are to be seen 
above and below. The parenchymatous cell below the ray tracheid 
is traversed by a filament of the fungus which probably gained 
entrance at the wounds. 
