258 SEMI-CENTENNIAL OF TORREY BOTANICAL CLUB 
This layer is continuous over the gall except where interrupted 
by small irregular patches or strips of cork that can not be re- 
moved easily. A burl with portions of the cork removed is shown 
in PLATE 4, FIG. I. The irregular patches of thin cork are out- 
lined to bring out by contrast the smooth, shining spermatiophore 
surface. А continuous area half 
an inch square can frequently be 
S . uncovered, disclosing the crust- 
ee like spermatial surface. Місго- 
Sm {оше sections three quarters of 
| an inch long have been made, 
| sp showing a continuous palisade 
| 
---- 
layer. A small portion of a sec- 
tion through a matured sper- 
matial layer is shown in TEXT- 
FIGURE 2. We have not ob- 
served in our sections that this 
effused palisade of spermatio- 
phores is limited by a definite 
marginal system of sterile cells. 
Spermatial primordia frequently 
extend from the margin of ma- 
tured areas as a plectenchyma 
of hyphae between the cork and 
<< cortical parenchyma ав illus- 
: trated in TEXT-FIGURE 1. The 
cortical cells immediately below 
jl l n D 
p. : US, 728) 
Фо 
NS Ady 
“66 
Fic. 2. 
Section through the cortex 
showing the spermatial layer. s, scleren- 
chyma; c, cork; sm, spermatia; sp, sper- 
the layer of spermatiophores are 
not spread apart by the hyphae 
as conspicuously as are those be- 
matiophores; b, basal tissue; cp, cortical n 
parenchyma. low the aecidium. We have not 
seen in any instance spermatial 
hyphae developing in the tissue overlying that in which the 
aecidia are being formed. Cross sections of the Virginia material 
developing both spermatial and aecidial fructifications on the 
same gall show that there is no sharp line of demarcation be- 
tween the two. In one burl there was a space of only 700 и 
separating them. The nature of the spermogonia of P. Cerebrum 
