8 4 



RESPIRATION 



active seedlings of the lupin, pea and wheat. The seeds were 

 germinated at about 20 C. and then exposed to various 

 temperatures, the carbon dioxide being estimated hourly for six 



70- 



60- 



35' 



00 



1 2 



HOURS 



FIG. 6. Respiration of the pea at various temperatures. 



hours (Fig. 6). At temperatures not exceeding 10 C. the output 

 of carbon dioxide is constant; from 10 C. to 20 C. there is a 

 continuous rise in the respiration of seedlings of all ages, which 

 rise is followed by a fall ; at temperatures above 20 C. and up 



