EXPERIMENTAL DATA ON ACIDITY DETERMINATION. 43 



TABLE 16 Continued. 



SERIES II. 



[Material collected at 2 h 30 p.m., April 10, 1911. Series begun at 3 p.m. Acidity at beginning- 

 Total 30.50; per gram, 0.65.] 



TABLE 17. Effect of diminished and increased oxygen supply. Opuntia versicolor. 



The experiments were carried on in New York with material sent from Tucson. The 

 joints were still turgid from the winter rains and had been kept where the water-loss was 

 minimized. In Series I, both juice and total acidity are given; in Series II, only juice 

 acidity. Acidity is given in terms of cubic centimeters of N /10 KOH per cubic centimeter 

 of juice or per gram fresh weight. 



SERIES I. 



SERIES II. 



