1888. TAN 
] BOTANICAL GAZETTE. 315 
ee lisade fm of the leaf. There are no bast cells in the 
Sor the ose: phe of the wing takes place ordinarily 
Meet ect nue has reached its length. The first indica- 
he - napreas is a little line of brown flecks at equal 
“sh ey on a me ridges at the corners. These may easily 
ke tc “Ry enticels, but on examination they are found 
ek. tom se of the wing which originates directly 
a. ae a. These are distributed thickly and evenly 
orl iositapiighos: sunken quite deep, as is usual on stems 
. with a thick cuticle. 
he Spe . brown spots extends along the entire inter- 
ives the . ross section through the middle of one of them 
ata a apiemehnanse one fig. 2 in secti 
rom this strikes across the end of the brown fleck 
: 25, the 
cells marked d are the phellogen cells, and by contrasting 
iginate in the chloro- 
hed out by the growing 
mediately about the air space are pus 
rm a debris around 
I 
co 
rk cells, are more or less broken, and fo 
— oe portion which have been shoved 
. his exudation 1s the pecu for 
ot s sufficient to form a ridge on eit 
e wing pushes its way, and when grown ap 
it as in a sort of socket. That this socket forms 
ct that if the latter be forcibly 
the wing, is seen from the fa 
aie from the stem, the socket always remains, and can 
nly be removed by cutting. (See fig. 28, @.) Continuing 
now the description from,the stage seen in fi , new cell 
ard the cir- 
phellogen layer tow 
between 
much material being expende 
ing summer, and from t 
erally a difference in th 
the second year’s growth being 1 
cells between the wings remain active un 
There is gen- 
f the wing; 
similation 
