2232 



Journal of Applied Microscopy 



fifteen or twenty minutes. Divide the resulting starch paste into three equal 

 lots. Cool the first lot to a temperature between 5° and 10°C. and add 10 c. c. 

 of the diastase solution ; set the flask in a place with a temperature of about 

 10°C. Pour a few cubic centimeters from the second lot into a test tube and 

 add a few drops of iodine solution, note the strong starch reaction. Test 

 another sample with Fehling's solution, for reducing sugar; they will be found 

 absent. Keep the temperature of this flask between 25° and 30°, add to it 10 

 c. c. of diastase solution and a few drops of chloroform ; test immediately as 

 before for starch and sugar. Observe the progress of the enzymatic action by 



Fig. 9. — Willow cuttings giown in the inverted position. Note the well 

 defined callus on the morphological lower ends. 



making similar tests at the end of 5 minutes, 15, 25, 40, 60, 90, and 120 min- 

 utes. At less frequent intervals test the progress of enzymatic action in the 

 cooler temperature. Note the total time required in each case for the complete 

 hydrolysis of the starch. 



The third flask of starch paste is to be hydrolysed to sugar by boiling with 

 dilute acid. Place the flask on the water bath and add three or four drops of 

 hydrochloric or sulphuric acid. After it has reached the boiling point, at inter- 



