The Microscope. 



175 



10). The palisade cells are delicate, not uniformly of the same 

 length, and filled with chlorophyll-bodies, of which many have 

 an oval, rather than the usual round form. The cells of the 

 loose parenchyma contain only a few chlorophyll-bodies, and 

 numerous minute starch-grains ; also oil and albumen. In 

 many of the cells bordering on the vascular system of the leaf 

 the bright yellow coloring-matter of the coptis is found. In a 

 few of the small inter-cellular spaces of the loose parenchyma 

 towards the lower surface of the leaf are small masses of resin. 



Fig. 11. 



Cross section of the stem of the leaf, cut midway of the stem. Drawn with the %• 

 in. objective, and the " C '* eye-piece. 



Stem of the Leaf.— The cuticle is thick, laminated, and in 

 the old stems has taken the peculiar tinge of yellow so common 

 in the plant. It is about ^Vo of an inch thick. The epidermis 

 is -g^-5- of an inch thick, and is composed of quite regular cells. 

 These cells are nearly square on the cross section, but on the 

 longitudinal are four or five times longer. Just beneath the 

 epidermis, and especially at the corners of the stem, is collen- 

 chyma; thick walled cells filled with chlorophyll-bodies. The 

 bulk of the stem is composed of simple oval cells of parenchy- 

 ma, generally rilled with starch-grains, a few chlorophyll-bodies 



