350 BOTANICAL GAZETTE [DECEMBER 
nasturtium, pansy, and poppy seed. It shows an acceleration of 
germination by temperatures which were above the maximum for 
complete germination. In contrast with fig. 7, fig. 8 (for larkspur) 
shows a retardation of germination as well as a great reduction in 
total germination by a temperature only 5°C. above the optimum 
for complete germination. 
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Fic. 7.—Average rate of germination of three lots of snapdragon seeds 
The harmful effect of a high temperature on the germination 
of nasturtium, pansy, poppy, and snapdragon seeds is shown by 
the fact that all of these seeds germinated more slowly even during 
the first few days with the temperature alternation 20°—30° C. 
(not shown in fig. 7, but about equivalent in average temperature 
to 22.5°C. constant) than at temperatures lower than 22.5° C. 
Pansy and poppy seeds germinated even less rapidly at 20°-30° 
