148 THE DESTRUCTIVE INFLUENCE OF 
replaced in earth. Much care was also taken when 
the seeds were sown to keep the batches distinct 
from one another, and to place them as much as 
possible under the influence of similar conditions. 
Spallanzani’s first experiments were made with the 
seeds of the Chick-pea, Lentil, Wheat-grass, Flax, 
and Clover. The water was heated slowly, and the 
seeds were taken out as soon as the desired tem- 
perature was attained, so that there was only a 
momentary exposure to the temperatures about to be 
cited. Of those which had been.exposed to 190° F. 
many did not germinate ; still fewer of the seeds that 
had been exposed to 201° produced young plants, 
whilst of those heated to 212° not one germinated. 
After the young plants which had been developed 
from seeds heated to lower temperatures had grown 
for thirteen days, their capability of resisting heat 
was tested in the manner described, and with this. 
result: Those whose roots had been momentarily 
exposed to 156° continued to live after they had been 
replanted, whilst others whose roots had been exposed 
to 167° and upwards speedily dried up and perished, 
though all alike had been replanted in carefully 
watered earth. 
These were the only complete experiments made 
by Spallanzani with plants and their seeds; but 
many other kinds of seeds only—including those of 
