78 INTERNAL ANATOMY OF INSECTS. 
writer, who, upon putting a thermometer into a bee-hive 
in winter, found it stand 27° higher than in the open air ; 
in an anthill, he found it 6° or 7° higher ; in a vessel 
containing many blister-beetles (Ca?it/iaris vesicatoria,) 
4° or 5° higher. A thermometer, standing in the air at 
14-° R., put into a glass vessel with Acrida viridissima, 
in nine minutes rose to 17°, and a similar result was ob- 
served with respect to other insects 3 . Dr. Martine says 
that caterpillars have but two degrees of heat above that 
of the air they live in b . Coleopterous insects are said 
to move slowly and with difficulty when the thermometer 
sinks to 36°, to become torpid at 34°, and to lose mus- 
cular irritability at a lower degree c . I have before ob- 
served that some insects will bear to be frozen into an 
icicle, and yet survive d : they share this power with 
reptiles, fishes, and amphibia. But, however small the 
excess of it in some insects above that of the medium 
they inhabit, it proves that they possess the power of gene- 
rating heat. Whether, like the warm-blooded animals, 
they generally possess that of resisting heat by perspira- 
tion, &c. is not so clear. Yet the heat to which some 
can bear to be exposed, basking at noon, as Dr. Clarke 
informs us % on rocky and sandy places, exposed to the 
full action of the sun, appears sufficient, if not resisted 
by some principle of counteraction, to roast them to a 
cinder. That bees perspire is well known, but probably 
not singly. 
When the respiration of insects is suspended by im- 
a Inch, c. iv. Ideen zu Eincr Zoochcmie, 68 — . 
'- On Thermom. 141. c Carlisle in Philos. Trans. 1805. 25. 
d Vol. II. p. 229. e Travels ii. 482. 
