232 PLANT ANATOMY. 
visible, that portion of the bark: which is traversed by them 
- Is termed the inner bark (Fig. 144 7, 149 7); the portion toward 
the exterior which is connected with it, and which mostly con- 
Serre] 
=a eI 
fe ci 
‘ord n 
aT 
rn RPh 
GEES | 
7 ae 
Fie. 149.—Transverse section through the bark of anolder stem of Ceratonia Siliqua 
L. k, sclerotized cork-cells; s, sclereids: m, medullary rays; sb, sieve-tubes; i, inner 
bark; mt, middle bark; a, outer bark (Moeller), 
sists of a mixture of parenchymatous cells containing chloro- 
phyll (bark parenchyma) and of mechanical cells (bast-cells, 
' With regard to the structure of the bark, compare especially Moeller, 
“ Die Anatomie der Baumrinden,” Berlin, Springer, 1884. 
