1921] HARRINGTON—GERMINATION 349 
same number of degrees hastened it. This dependence of the 
rapidity of germination upon temperature was much more marked 
with some kinds of seeds that with others. Figs. 5-8 show the 
average rates of germination at different temperatures of a number 
of different lots each of balsam, cypress, snapdragon, and larkspur 
Phe 
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oa guleeescsy se AL 
—— 
G y 
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20 
40 
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Fic. 6.—Average rate of germination of two lots of cypress seeds 
seeds, and illustrate differences in sensitiveness to temperature 
conditions. Fig. 5, for balsam, is typical also for mignonette, 
petunia, and portulaca, in so far as the range of temperatures for 
complete germination is the same. Cypress seeds (fig. 6) ger- 
minated more rapidly than any other kind, and almost as rapidly 
at 15° as at 30°C. Fig. 7, for snapdragon, is typical also for 
