NUCLEUS-SHEATH, 205 
and likewise possesses mechanical functions, is also to be con- 
sidered here. In these organs, namely, or at least in those cases 
which more nearly concern us, all the bundles, or a predami- 
nating number of them, are inclosed by a single row of cells 
(Sarsaparilla), or, by a layer, the endodermis, which is seen to 
cones veniees 
ESE AT RS 
Fie. 122.—Rootlet from Helleborus viridis; a, epiblema; b, fundamental tissue; c, 
central bundle; k, endodermis. 
be narrow on a transverse section and consists of but a few cells 
(Galanga), All the vascular bundles are located within the en- 
dodermis, for instance, in Radiz Sarsaparille, Rhizoma Caricis, 
in the rootlets of Actea spicata (Fig. 120), Aconitum (Fig. 121), 
Helleborus (Fig. 122), Serpentaria, Valeriana, and Veratrum 
(Fig. 119). On the other hand, in Rhizoma Calami, Rhiz. 
