748 



BOTANY AND PHARMACOGNOSY. 



simple pores ; pollen grains oblong or ellipsoidal, very prickly, 

 about 35 fi in diameter; collenchymatous cells with yellowish- 

 brown resin and tannin masses. 



3. Pollen Grains Wanting. 



* Fibrovascular Tissue Present. 



88. LAPPA. — Light yellow ; parenchymatous cells with irreg- 

 ular crystalloidal masses of inulin ; tracheae few, reticulate, some- 

 times associated with few narrow sclerenchymatous fibers. 





*=«», 



Fig. 297. Aspidium: P, parenchyma containing starch grains; S, starch grains; 

 T, tracheae; H, hypodermal cells with thickened walls and simple pores, C, yellow, thick- 

 walled cells of chaff. 



89. SENEGA. — Dark yellow ; odor penetrating ; slightly ster- 

 nutatory ; sclerenchymatous fibers thick-walled, non-lignified, with 

 oblique simple pores ; tracheae short, lignified, with simple and 

 bordered pores; medullary-ray cells somewhat lignified, with 

 large simple pores. Quillaja (Figs. 281, C ; 300, G; 315) is dis- 

 tinguished from senega by having large monoclinic pyramids of 

 calcium oxalate, starch and numerous lignified bast fibers and 

 stone cells. 



