500 SiLBERBERG '. STIMULATION OF STORAGE TISSUES 



control flask was 94.093 ex. Subtracting the bulk of potato, the 

 volume of gas present would be 84.857 ex. If 13.072 c.c. of the 

 total gas volume, 84.857 c.c, was carbon dioxide, the per cent, of 

 carbon dioxide present would be 15.43. This is an example of 

 the method used in all the analyses and calculations, the results 



V 



of which will be found on page 499. 



These investigations are merely the introduction to what might 

 be done in the way of experiments showing the effect of zinc sul- 

 phate stimulations upon the respiration of storage tissues, but they 

 serve to indicate that fourteenth-normal solutions, or any solutions 

 stronger than that, inhibit the respiration of the storage tissue of 

 potato. A sixteenth-normal solution stimulates respiration.^ Fur- 

 ther than that, the results so far obtained do not justify any definite 

 statements. It is hoped that at some future time the data already 

 obtained m these investigations may be amplified and the work 

 carried on to a far greater extent. 



Botanical Laboratory, Barnard College, 

 Columbia University, New York, 



^ 



