at different Degrees of Constant Temperature. 249 
Collomia. Germinated six days and three-quarters after the 
sowing. 
Lepidium. Germinated on the third day. 
Linum. One seed commenced on the second day, several 
others on the fourth. 
Maize. One seed on the tenth day, two others on the twelfth, 
and others subsequently. 
Melon. Did not germinate. 
Nigella. Germinated on the fifteenth day. 
Sesamum. Did not germinate. 
Sinapis. Germinated at the end of three days and a half. 
Tberis. On the sixth day. 
Trifolium. Some seeds on the fifth day, others on the sixth, 
the eighth, &c. 
At a temperature of 12° to 13°. 
The same kinds of seeds were sown and watered on the 15th of 
July, in the same manner as the preceding, but at a temperature 
which in the cellar, from the 15th to the 30th of July, was 13°°66 
in the air, and 12°-6 in the soil,—the extreme variation in the air 
being 1-0, and in the soil 0°°8. During the first three days, 
the mean in the soil was 12°-9: this refers especially to four of 
the species mentioned below. The results were :— 
Collomia. Germinated on the sixth to the seventh day. 
Lepidium. Germinated after about a day and three-quarters. 
Linum. Germinated in about two days and three-quarters. 
Maize. Two seeds out of seventeen germinated at the end of 
the fifth day; and on the seventh day half had germinated. 
Melon. Did not germinate, not only from the Ist to the dlst 
of July, but also during the month of August. 
Nigella. The ninth day (at the end) a fourth part of the seeds 
germinated. 
Sesamum. Germinated abundantly at the end of the ninth day. 
Sinapis. Germinated after one day and three-quarters. 
Iberis. From three and a quarter to four days. 
Trifolium. Germinated at the end of the third day, unequally. 
The uncertainty which existed in regard to four of these 
sowings, induced me to repeat the experiment at once. 
Lepidium, at 12°-9, sprouted in one day and three-quarters, 
as before. 
The linseed failed; but on again repeating the experiment at 
13°5, it germinated at the end of one day and three-quarters. 
The mean, with the preceding experiment, is two days and a 
quarter, at 13°2, 
