143 



PEPPER 



walls being thickened and commonly referred to as " beaker cells. 

 The perisperm consists chiefly of radially elongated cells containing 

 numerous starch grains which are 0.002 to 0.006 mm. in diameter; 

 some resin cells; cells containing needle-shaped crystals of piperine, 

 and in the outer layers small aleurone grains. 



Powder. (Figs. 63 and 64.) Grayish-brown; stone cells nearly 

 isodiametric, uniformly thickened or with only three walls thick% 

 ened, the contents consisting of yellowish-brown tannin masses, 



am 



ut- 



I 



*.* 



08 



FIG. 63. Black pepper: ep, polygonal cells of the epicarp, beneath which are the 

 hypodermal stone cells (osi); bf, elongated bast fibers; bp, short bast fibers; 

 sp., tracheae with spiral markings; ist, stone cells of the endocarp; is, as, frag- 

 ments of tissues beneath the endocarp; am, parenchyma cells of the perisperm 

 containing starch grains; A, starch grains; p, oil cells.^After Moeller. 



which give a blue reaction with ferric ammonium sulphate solution; 

 starch grains spheroidal or angular, from 0.001 to 0.00$ inm. in diam- 

 eter; parenchyma with remains of chromoplastids and reddish- 

 brown amorphous masses; oil-secretion cells with sub0rized walls; 

 oil globules numerous. 



Constituents. Volatile oil 1 to 2 per cent, containing dipentene, 

 phellandrene and a peculiar terpene; the alkaloid piperine, 4.5 to 



