STUDY OF YUCCA ANGUSTIFOLIA 149 



alkalies, dissolved by sulphuric acid with a red coloration; 

 chloroform left a brownish residue which, on weighing, yielded 

 0.4 per cent. This residue was moistened with a few drops 

 of concentrated sulphuric acid, and changed to a red-violet 

 color characteristic of saponin. 



A certain portion of the aqueous extract was rendered alka- 

 line, and heated over a water bath with Fehling's solution. 

 The precipitated copper was collected on a weighed filter, 

 dried, and incinerated, and the glucose estimated gravimetri- 

 cally from it. It yielded 1.592 per cent. Another portion of 

 the aqueous extract was acidified, boiled, and potash added 

 until the solution was alkaline to litmus paper; then the liquid 

 was mixed with Fehling's solution and heated over a water 

 bath. The percentage of saccharose or other substances which 

 reduced the copper was calculated by difference. It amounted 

 to 0.929 per cent. 



The resin separated by acetic ether was an opaque sub- 

 stance, greenish-yellow in color,, and insoluble in ether. The 

 resin was dissolved in water and frothed on shaking. The 

 emulsion in this case was not quite so permanent, as a slight 

 resinous sediment settled after a time, possibly due to changes 

 in the resin through oxidation. 



Extract (3), the Green part of the Leaf. 



The dried residual powder was macerated by the aid of 

 heat with Squibb' s stronger alcohol. When warm the alco- 

 holic extract was clear, but on cooling the solution became 

 cloudy, and a creamy-white fine precipitate settled. The alco- 

 holic extract was neutral in reaction. It was evaporated in a 

 current of carbonic acid, dried, and weighed. A certain part 

 of the residue was incinerated and the ash determined. 



TOTAL SOLIDS. 



Alcoholic residue dried at 100 C 3.80 per cent. 



" 110 C 3.80 



" ash 0.15 " 



The alcoholic residue was treated with cold distilled water. 



