138 



SCIENTIFIC AND APPLIED PHARMACOGNOSY 



late from scars of bud-scales, upper surface with numerous large, 

 sometimes repressed sears, under and side portions with numerous 

 roots and few root-scars; fracture short; internally light brown, 

 cortex about 0.5 mm. thick, central cylinder somewhat porous, and 

 with numerous scattered fibro vascular bundles; odor heavy, distinct; 



FIG.- 61. Transverse section of central cylinder and portion of cortex of root of 

 Cypripedium parviflorum pubescens: E, epidermis; H, hypodermis; Ca, 

 Raphides of calcium oxalate; P, parenchyma containing starch (St)', En, 

 endodermis; F, lignified sclerenchymatous fibers; T, tracheae; B, non-lig- 

 nified, thick-walled fibers exterior to sieve groups; L, peripheral layer of 

 central cylinder. The latter usually consists of 6 to 8 radial fibrovascular 

 bundles. 



taste bitter, somewhat pungent, 

 are slightly cutinized (Fig. 61). 



The walls of the endodennal cells 



