Prof. J. Le Conte on the Freezing of Vegetables. 85 
which had become a lump of ice. Spallanzani found that expo- 
sure to a temperature of -38° or even —56° Fahr., did not de- 
stroy the fertility of the ova of silk worms; and the eggs of the 
slug have been subjected to a cold of —40° Fahr. without injury. 
The following experiment upon caterpillars, tried in Sir John 
Ross's voyage, seems to be perfectly satisfactory on this point. 
Thirty larvee of the Laria Rossii were put ina box, and exposed 
to the winter temperature for three months; on bringing them 
into’ the cabin, every one of them returned to life and crawled 
about. They were again exposed to an atmosphere of —40° 
Fahr., and instantly became re-frozen; after a week, they were 
brought again into the eabin, and twenty-three returned to life. 
ese were again exposed and re-frozen; and, after being solid 
for another week, eleven of them recovered on being brought 
into the cabin.’ A fourth time they were frozen, and only two 
survived. * 
_The foregoing facts appear to indicate, that the power of re- 
Vivification after the complete congelation of the fluids, is con- 
* Vide Carpenter’s Principles of General and Comparative Physiology. 2nd ed. 
—_ 1841. pp. 158, 174 and 175. 
a when frozen, ; ; 
of the hypothesis that such a vital principle may exist im org: bodie 
=o enable a even while inactive and displaying no other signs of site 
that qeasively the influence of physical forees.” Prof. Paget thinks, that the { 
ig © temperature of eggs may be — gery the freezing Ser ae 
3 yi inciph to some ' se ie acon arr 
duskas ee due, not to rf Mera ——. a ph en Loree : ith 
eae ee et 
*t OF near 32° eannot take place,” (vide Phil. Trans. for 1850, P. jet 09: 
