and then filtered so as to separate them from the fatty substances 

 and chlorophyl that were dissolved in the alcohol. An aliquot pare 

 of the filtrate was taken in order to estimate, with Feh ling's solution, 

 the reducing sugars, and another part was hydrolised with a dilute 

 solution of hydrochloric acid to determine saccharose. The sample 

 treated with warm alcohol for the separation of sugars, was extracted 

 with cold water to obtain the so-called dextrine, which was then 

 inverted into reducing sugars. Finally, the same sample, from which 

 the dextrine had been extracted, was digested with a dilute solution 

 of hydrochloric acid, to convert the starch into reducing sugars. In 

 this way the reducing sugars are produced not only from starch, but 

 from all other hydrolisable carbohydrates which are insoluble in al- 

 cohol and cold water. The further procedure of analysis was carried 

 out in the usual way with Fehling's solution. 



It is necessary to note here that the roots contain a large 

 amount of iron, which produces ferrous compound in hydrolysis with 

 hydrochloric/ acid. The presence of the ferrous compound is easily 

 recognized in neutralizing the hydrolised solution of the starch from 

 the roots ; on adding a solution of sodium hydroxide to the hydrolised 

 solution of starch, the precipitates of ferrous hydroxide mixed with 

 ferric hydroxide have a dark green appearance. Morison, C. G. T. 

 and Dayne, H. C., (" Ferrous Iron in Soils," Jour. Agr. Science Vol. 

 IV. p. 97 1914), find that iron compounds m soils yield a large 

 quantity of ferrous iron when the soils are digested with acid in the 

 presence of organic matter. It is, therefore, to be expected that 

 the roots of the rice plant which have a very high percentage of iron, 

 produce ferrous compounds in digestion with acid. In neutralizing 

 the hydrolised solution of starch, the ferrous iron is not precipitated 

 entirely. Thus the reducing sugars, as well as the ferrous salts 

 contained in the filtrate of the neutralized solution, act on the Fehling 



solution. Therefore a little excess of sodium hydroxide is to be 



/ 

 added to the hydrolised solusion of starch until no precipitates are 



