
250 BOTANICAL GAZETTE [APRIL 
seriously with the subsequent growth of the seedlings. It is 
clear, however, that the gas has a marked influence upon dry 
seeds. The extent of the influence depends upon the amount 
of gas per cubic foot and upon the time the seeds are subjected 
to its influence. After sixty days the percentage of germination 

a é 
Fic. 3.—a, control; 4, seeds that were one year in gas from 0.3332" KCN per 
cubic foot; ¢, seeds that were one ead in gas from 18™ KCN per cubic foot. 
was gradually reduced, and the subsequent growth of seedlings 
was likewise retarded. The greater reduction in the percentage 
of germination, as well as in retardation of growth, depended 
upon the length of time of exposure to the gas and upon the 
amount of gas present. At the end of eight months the seeds 
‘in the gas from one gram of KCN had practically lost their ability 
to germinate, since only one in ten was capable of even slight 
germination, and those were too feeble for subsequent growth 
(fig. 2,¢).. lt the gas was generated from only one third of a 
gram of KCN per cubic foot, the seeds retained their ey to 


