196 PLANT ANATOMY. 
ened to the extent of the disappearance of the lumen or vavity, 
and contain air. They possess a supporting capacity which is 
almost equal to that of wrought-iron, and a tenfold greater 
ductility than the latter, and are therefore in themselves ad- 
mirably adapted for the mechanical purposes of the plant. 
“Fie. 110. Fie. 111. 
Fie. 110.—Typical bundle of bast-cells, at a@ in transverse section, at bin longitudinal 
section; c, section of a bast-cell, showing the striping of the membrane and oblique 
pits (Tschirch), 
Fie. 111.—Bast-cells of Corchorus olitorius (Jute), with a lumen or central cavity of 
varying width, at the top in transverse, and below in longitudinal section (Tschirch). 
Moreover, they are always united to- form structures which are 
in nowise inferior to the best constructions of our engineers.’ 
‘ With regard to the firmness of bast-cells, compare Schwendener’s 
