PREFACE IX 



B shows that the quantity of oxygen absorbed is about 

 the same as that of the carbon-dioxide given out, is only 

 approximately true in the case of seeds, and hardly 

 justified, perhaps, by the results of this particular ex- 

 periment, for analysis of the gases 4n the tubes appears 

 to show that respiration ceases in B when the concen- 

 tration of COs has reached 10-15 per cent. The state- 

 ment is, however, true for ordinary respiration. 



P. F. F. 



