58 



ACIDITY AND GAS INTERCHANGE IN CACTI. 



TABLE 33. Intramolecular respiration. 



The material used was 12 mature joints of Opuntia versicolor of the previous season's 

 growth, having a fresh weight of 320 grams. Respiration was observed in air and in pure 

 nitrogen at 21 and 35 C. The experiment was carried on in New York with material sent 

 from Tucson. 



TABLE 34. Intramolecular respiration. 



Carried on in New York with material sent from Tucson, consisting of 9 mature joints of 

 Opuntia versicolor, of the previous season's growth, with a fresh weight of 200 grams. Respi- 

 ration was observed in air and in pure nitrogen at 21 and 35 C. 



