298 
MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 
although they retain a tinge of grey colour for a much longer period; the yellow 
bands on the body and thorax are at first quite white, and it is not until an hour or 
two has elapsed that the principal yellow band on the thorax begins at length to gain 
colour, while it is several hours before the yellow bands acquire their full shade or 
degree of colour. During all this time the bee continues in an enfeebled state and 
takes no part in the business of the nest, but seeks for itself the warmest place among 
the combs, and it is not until sometime after it has acquired its proper degree of 
colour that it becomes active like the other bees, and is able to maintain its own 
proper temperature. It is thus evident, that the same principle which has been shown 
by Dr. Edwards to prevail with regard to the young of some of the mammiferous 
animals, that they are unable for a certain period after birth to generate and maintain 
within themselves a proper amount of temperature, but require to be cherished by 
external warmth, regulates also the development of the individuals of this family of 
Hymenopterous insects, from their pupa or nymph to their perfect state, and further 
tends to prove to us how universal and simple are the great laws which regulate the 
continuance of animal life. It is a curious fact that these bees do not incubate on the 
cells which contain only larvae, the temperature of the atmosphere of the nest being 
sufficiently high for them in that condition ; consequently the larvae at an advanced 
period do not require so high a temperature before changing into nymphs as that 
which has just been shown to be required by the nymphs before coming forth as per- 
fect insects. This will be shown in some observations made on larvae in the nest 
now under examination, at the same time with those just described, and also with 
others which were made on nymphs. The temperature of the atmosphere being 7 ®°, 
some of the cells which were open and contained larvae were exposed in the nest, 
and the Nurse Bees therefore covered them lightly with dried grass, of which the nest 
of this species of Bombus is usually composed ; but when the temperature of the 
atmosphere a few hours afterwards had risen to 73°'5, most of the dried grass with 
which these cells had been covered was removed, and the larvae were more exposed ; 
the temperature of these cells and the larvae being 77°'4, while that of the cell of a 
nymph, with the Nurse Bee upon it, in another part of the nest was 92°, and subse- 
quently when four large females were nursing around it was 94°T, the temperature of 
the atmosphere being still 7 2°‘5. 
When there are no longer any nymphs which are soon to be developed into perfect 
insects the necessity for generating a larger amount of heat is diminished, and the 
Nurse Bees remain in a state of quietude ; the temperature of the nest is then much 
lower than when young bees are about to be produced. This was the case on the 
14th of July; the atmosphere was then 69°, while that of the nest was in no part 
higher than 7 2 0, 5 ; and even when the bulb of the thermometer was in contact with 
the bodies of several of the bees, the mercury scarcely rose to 73°*5, while at 12 o’clock 
on the preceding night, when the atmosphere was 68°, and several young bees were 
soon to come forth, the temperature of the box was 70°‘5, and that of some bees 
