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MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 
Staphylinus olens , and S. erythropterus, Linn. 
Both these species of Rove Beetles have a comparatively low temperature, and it is 
often difficult even to detect the existence of distinct temperature in these insects, 
unless the individuals have become considerably excited. I have never yet examined 
S. Olens in the autumn before it retires to its hybernaculum, but in a specimen found 
in April, the temperature of the atmosphere being 60 o, 2, that of the insect was 61 0, 2. 
I could seldom find it rise higher, and it was often difficult to detect its existence at 
all. In S. Erythropterus I have seldom found the temperature higher than about ’5 
above the atmosphere. It must thus be seen that there is a marked difference between 
the power which these insects possess of generating heat, and those which are more 
constantly in the open air ; and when we examine the Carahi and Tenehriones , this 
difference of power is still more remarkable. 
Cardbus monilis , C. violaceus, and C. nemoralis, Linn. 
June 18, 1834. — A specimen of the Ground Beetle, Car abus monilis, without being 
touched with the fingers, was carefully placed in a stoppered phial, the temperature 
of which, as well as of the atmosphere, was 67 0, 4. When the bulb of the thermo- 
meter was pressed against the under surface of the insect the mercury was not per- 
ceptibly affected, nor was there any change in the temperature of the closed phial 
during five minutes, all which time the insect was in a state of great excitement. 
This observation being made precisely as in the cases with the hymenopterous insects, 
the temperature of the Carabus, consequently, is exceedingly low. It ought to be 
remarked, however, that this insect had fasted during eighteen hours, and of course 
could not be expected to generate so great an amount of heat as the recently fed 
specimens. A second specimen, which had been recently captured, was then placed 
with the first in the same phial, and within a few minutes the atmosphere of the phial 
was raised to 6 7°‘6, or - 2 of a degree above the previous'temperature. A specimen of 
Carabus violaceus was then added to the number, and the three insects continued in 
a state of great excitement for several minutes, when the inside of the phial was 
found to be 67 °' 7 , or '3 of a degree above its original standard; but only a very slight 
additional effect was produced on the thermometer when applied to the body of the 
insects. 
April 11, 1836, 3^ p.m. — I examined a single female specimen of Carabus nemoralis 
which had recently been captured. The insect was lying quiet when I made the first 
observation, by applying the thermometer to the under surface of its abdomen. 
The temperature of the atmosphere was then 61°‘6, and that of the insect 61 0- 8. The 
insect then became active, and at the expiration of half an hour was 62 0, 8, that of the 
atmosphere having risen to 62 0, 5, while in ten minutes after this observation, the 
atmosphere being 63°, that of the insect was 63 0, 4. The difference, therefore, in this 
specimen in a state of great excitement, was only *4 of a degree, while, as we have 
