110 THE UNIVERSITY SCIENCE BULLETIN. 



reagent. The characteristic yellow stain deepened when a drop 

 of ammonium was added to sections which had been mounted in 

 nitric acid. Clusters of crystals of calcium oxalate were numerous 

 in the cells of the primary cortex, the pericycle, and the second- 

 ary medullary rays. No volatile oil, glucosides, mucilage, tannin, 

 starch nor alkaloids were found to be present in the root. 



The Leaf. 



Similar tests were made on sections of the leaf. Certain globules 

 which stain red in Sudan III and pink in alcannin, like oil, were 

 present in the cells of the epidermis, and photosynthetic tissue 

 (fig. 73, q'). These globules stain unevenly like similar globules 

 in the stem. The globules are soluble in xylene, chloroform, and 

 ether. Other tests did not indicate the presence of saponifying 

 oil nor resin in these globules. 



There are other globules, most of which are quite large, in the 

 epidermal cells, which did not stain with Sudan III nor alcannin, 

 and which were not soluble in xylene, chloroform, nor ether; but 

 these globules in sections left in the electric oven formed crystals 

 of cuprous oxide with Fehling's solution continuously for three 

 days, the presence of glucosides thus being indicated (fig. 73, r'). 



The presence of reducing sugar was demonstrated by the for- 

 mation of cuprous oxide crystals in the cells ot the phloem and 

 photosynthetic tissue when sections of the leaf in Fehling's solu- 

 tion were heated to the boiling point. 



The characteristic stain of protein developed with Millon's 

 reagent, or nitric acid with the addition of ammonium, in the cell 

 contents of the phloem of leaf sections tested. 



Clusters of calcium oxalate crystals occur in great abundance 

 in the border parenchyma cells of the veins, and the water-storage 

 tissue. In a general drawing of a bleached leaf, the greater part 

 of the leaf is darkened by the numerous crystals mapped out 

 along the veins and veinlets of the leaf (fig. 96). 



The other tests applied did not indicate the presence of volatile 

 oil, mucilage, tannin, starch nor alkaloids in the leaf. 



The Hairs of the Leaf and Stem. 



In the cells of the basal portions of the clothing hairs (figs. 16, q', 

 and 77, c",) and of the glandular hairs (figs. 17, q', and 78, c") of 

 the stem and the leaf are globules which stain with Sudan III 

 and alcannin. 



