96 



PLANT ORGANS OR PARTS OF PLANTS. 



walled, usually tinged with brown or yellow, and have 

 one wall thicker than the other ; they are richly pored and 

 do not contain any starch grains. Their average diameter 

 is about 20 to 30 microns, and they run from four to 

 eight times as long as broad; some are much shorter, 



rtmn„--,r-^f~f-^r C>S XX 



Fig. 14. — Powdered Sarsaparilla. 

 Epi, Epidermis; H, hairs; W. P, wood parenchyma; C, crystals; 

 'S, starch; Endo, endodermis; Fibr, fibers; Hyp, hypoderm; P.D, 

 pitted ducts; TR, tracheids; P, P', P^, parenchyma; ST, hypoderm 

 stone cells; V, fragments of ducts. 



resembling stone cells. The cortical parenchyma tic cells 

 are uniformly thinner-walled, though the wall is not very 

 delicate ; in general outline they are usually cylindrical, 

 some short, others much longer. The average cross-section 

 of this parenchymatic tissue shows cells whose diameters 

 range from about 50 to 100 microns, the cells nearer the 



