CONTENTS. XV 



CHAPTER X. 



PROTEIDS. AMIDES. AMMONIA. NITRATES, &C. 



Literature. Practical classification of nitrogenous plastic sub- 

 stances. Qualitative examination for proteids insoluble in water, soluble 

 in dilute alkali for proteids soluble in water for peptones and albu- 

 moses for amides for ammonia, nitrates, nitrites. Estimation of 

 proteids of peptones and albumoses. Estimation of amides. Estima- 

 tion of ammonia, nitrates and nitrites. Experiments on nitrogenous 

 metabolism. Qualitative examination of Onobrycbis sativa for proteids 

 &c. Comparison of amounts of proteids, peptones, amides in seeds of 

 Onobrycbis and in shoots of the same grown under various conditions. 

 Comparison of amounts of ammonia, nitrates, nitrites in shoots of 

 Onobrychis from plants variously treated . . pp. 249 26O. 



CHAPTER XI. 



*b 



OILS AND FATS. GLYCERINE. 



Literature. Extraction of oils and fats. Qualitative examination of 

 benzene extract. Reactions of glycerin. Quantitative examination. 

 Determination of total oils and fats of free fatty acids of glycerin. 

 Experiments. Determination of oils and fats in seeds of Lepidium 

 in seedlings of Lepidium, young and old . . . pp. 261 265. 



CHAPTER XII. 



TANNINS AND GLUCOSIDES. 



Literature. Extraction of tannins and glucosides. Many different 

 bodies included under heading tannin and glucoside. Qualitative tests 

 for tannins. Qualitative tests for phloroglucin. Eenioval of tannins 

 before examining for sugars. Determination of whether a tannin is a 

 glucoside or not. Glucosides. Identification of salicin. Examination 

 for certain sugars. Experiments. Testing extract of willow-bark for 

 tannin, salicin. sugars. Estimation of certain sugars in young and old 

 fruits of Musa sapientum ...... pp. 266 275. 



