358 BOTANICAL GAZETTE [DECEMBER 
lower temperature is somewhat more favorable. Such considera- 
tions make it possible to test all the kinds of seeds investigated 
with approximately optimum conditions by maintaining only 
three different temperatures. These three temperatures may be 
either 15°, 20°, and 22.5", or 15°, 20°, and 30° C., according as 
petunia and sweet pea seeds are to be tested with a constant tem- 
perature (22.5°) or with an alternation of temperatures (20°-30° C.). 
It should be emphasized, however, that probably more uniformly 
good results would be obtained by using for each species the tem- 
perature indicated in table IV. 
GREENWICH, CONN. 
