V 
CLIMATE AND HYBERNATION 
103 
the coldest 46°. The lowest point to which the thermometer 
fell was 4i°.5, and occasionally in the middle of the day it 
rose to 69° or 70°. Yet with this high temperature almost 
every beetle, several genera of spiders, snails, and land-shells, 
toads and lizards, were all lying torpid beneath stones. But 
Ave have seen that at Bahia Blanca, which is four degrees south¬ 
ward, and therefore with a climate only a very little colder, 
SKINNING UJI OR WATER SERPENTS. 
this same temperature, with a rather less extreme heat, was 
sufficient to awake all orders of animated beings. This shows 
how nicely the stimulus required to arouse hybernating animals 
is governed by the usual climate of the district, and not by the 
absolute heat. It is well known that within the tropics the 
hybernation, or more properly aestivation, of animals is deter¬ 
mined not by the temperature, but by the times of drought. 
Near Rio de Janeiro, I was at first surprised to observe that, 
a few days after some little depressions had been filled with 
Avater, they were peopled by numerous full-grown shells and 
beetles, which must have been lying dormant. Humboldt has 
related the strange accident of a hovel having been erected 
over a spot where a young crocodile lay buried in the hardened 
