at Different Degrees of Constant Temperature. 247 
The cavity 8, sown with linseed and maize, varied from 2°8 
to 3°°2 (mean 3°). During the seventeen first days the tempe- 
rature was steady at 8°1, and the linseed germinated on the 
seventeenth and eighteenth days, in tolerable quantity. The 
maize did not germinate. 
The cavity y contained Nigella, Sesamum, and Sinapis. The 
temperature usually varied between 2°°6 and 3°2; but on the 
sixth day of the experiment an accidental cause of increased 
heat occurred, raising the temperature to 5°. The Nigella and 
Sesamum did not germinate. Three seeds of Sinapis germinated 
on the ninth day, or rather on the eighth and a half day ; on the 
seventeenth one more germinated; the rest were unchanged. 
Finding the experiment useless, I again sowed Sinapis, at 2 
o’clock on the 18th of March, in an additional vessel placed in 
the cavity y. One seed germinated on the sixth day, another 
on the thirteenth, subsequently two more, which proves but 
little, for 60 or 80 grains were sown. After the experiment the 
temperature gradually rose to 8° during twenty-eight days, and 
oh seeds which had not previously germinated did not then 
0 So. 
At temperatures of 4°°2 to 61. 
The same species were placed in the lateral cavities furthest 
from the reservoir of ice, also in three vessels. 
a varied from 4°°6 to 6°-1 (mean 5°35). It contamed Col- 
lomia, which germinated on the seventeenth day in tolerably 
large proportion (nearly half), and Lepidium, which germinated 
on the eighth day in tolerable abundance. 
B varied only from 4°°7 to 4°°9. It contained maize, which 
did not germinate, and linseed, which germinated on the seven- 
teenth day in the proportion of nearly a fifth of the seeds sown. 
y varied from 4°-2 to 4°-9 (mean 4°55). It contained Ni- 
gella, Sesamum, and Sinapis. None of these germinated, not 
even the Sinapis. Evidently the seeds of the latter species, which 
sprout so readily, had suffered; for a month afterwards, when 
the temperature had risen to 8°, only a single individual showed 
itself out of thirty or forty sown on the 6th of March. 
The moisture had probably been too great in these three cavi- 
ties, as in those in which the mean was from 2°°6 to 3°2, just 
alluded to. On the 9th of May, twenty-eight days after the 
experiment, of all the sowings there only remained a single plant 
belonging to Sinapis. 
At a temperature of about 5°°7. 
From the 6th of March to the 11th of April, the temperature 
of the cellar in which the experiment was made varied only from 
