248 BOTANICAL GAZETTE [APRIL 
bell jars under the same conditions as in the experiments, with 
the exception that no KCN was placed in the dilute sulfuric acid. 
-The results are best expressed in the following table: 
TABLE II. 
Dry seeds treated with peas bocs acid gas for ae periods of time: temperature 
oughout about 18° 





ee ee ee fe | Pee ohn 
foot to gas ecient germination germination seedlings 
G,000))5 ca, fo) 24 hours 24 hours 100 normal 
OeF8 So as 15 days ro Seah fe 100 accelerated 
THO oo. gi aq St eae 100 wie 
[2 We ly ee es Bee 60:5." op Sa 3 aes 100 celer. 
POCO Cs 60.°2" 24°" ve 100 a aipeane 
U333 60 rss Ba oats aq.“ 75 slightly coene 
DOO cee Gr aS ss ae Bieca, 60 greatly retarde 
eet edo 2. heres ys ee 50 retarded half 
HOO ons 24000 0, ey 96..." 10 very slight 
0.333 S05 0s 2a a 40 20 none 
T00022005- 0 S6g ns 2400" no germination te) 





From the foregoing table it will be seen that the seeds were 
constantly under the influence of the gas for from fifteen days 
to one year. The strength of the gas was constant in each jar, 
z. e., it did not vary except possibly by the absorption of a small 
quantity of the gas into the seeds and into the few cubic centi- 
meters of dilute acid used in generating the gas. It is surprising 
that the seeds should germinate more readily after they had 
been exposed to the gas for a few days, although the same 
phenomenon was observed in the action of ether upon the germi- 
nation of seeds.’ 
At the expiration of sixty days the acceleration of germina- 
tion had passed its maximum, and shortly after began to be 
retarded, until at the end of two hundred and forty days germi- 
nation practically ceased for those seeds that were exposed to 
the gas from one gram of KCN per cubic foot (fig. 2,¢). The 
seeds that were in the weaker charge of gas continued to 
7 TOWNSEND: The influence of ether upon the germination of seeds and spores. 
Bot. Gaz. 27: 458. 1899. 

