328 
MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 
for the insects to bear, since nearly the whole of them immediately retired beneath the covering of the nest, and 
there was scarcely a single ant to be seen. On the 2nd of September I repeated my observations on the same 
ant-hill. On this occasion the day was very gloomy, with steady light rain, and the temperature of the atmo- 
sphere at 11 o’clock a.m. was only 54°. The temperature of the ant-hill varied but little in its different parts 
but it was now greatest near the surface. At a depth of one inch it was 6 5°, at two inches 66°, below which 
it gradually diminished. At this time I also examined another nest of the same species, but which was about 
twice the size of the first. The atmosphere being, as before stated, 54°, the mean temperature of this nest, 
when the insects were a little excited, was 74°. 
During the summer and autumn of the present year I have repeated my observations on the temperature of 
the bee-hive, and have found but little variation in its average amount at similar periods in the two years. I 
have also examined the nests of Bombus lapidarius, and Bombus sylvarum, and in both have found that the 
ordinary temperature, which is about 10° or 15° above that of the atmosphere, is considerably increased during 
the period of incubation, exactly the same as in the nest of Bombus terrestris. 
On the following day after examining the nest of the wasp, I examined the temperature and pulsation of the 
larva of the same species. The specimens examined had been removed from the nest on the previous evening, 
but had not been removed from their cells. The results are given on the accompanying table. I examined 
also the larva of the hornet, Vespa Crabro, Linn., which was still contained in its cell, but had been some days 
removed from the nest. In this instance the temperature of the larva was found to be about 2 0- 5 Fahr. above that 
of the atmosphere, but its rate of pulsation was only thirty-two beats per minute. I should have attributed this 
low rate of pulsation to the specimen having been so long removed from the nest, had not the rate of pulsation in 
this larva been examined by my friend Mr. Orsborn a few days before, and almost immediately after the 
specimen was obtained from its nest, and found at that time not to exceed thirty-three or thirty-four beats per 
minute. These facts therefore are in accordance with the observations on the larva of Anthophora retusa and 
Bombus terrestris, and also accord with other observations on the larvae of that very destructive tenthredo or 
saw fly Athalia centi/olia, Klug ; which has been so obnoxious to the agriculturist by destroying his crops of 
turnips during the last three summers. 
London, November 1th, 1837. 
TABLE.— TEMPERATURE OF LARVAL 
No. of Exp. 
Name of Species. 
Period of 
observation. 
No. of 
Specimens. 
Atmo- 
sphere. 
Soil. 
Insect. 
Difference. 
Pulsation. 
Remarks. 
1 
July 
i 
o 
70* 
o 
725 
o 
2-5 
32 
Full grown; has fasted three or four days. 
2 
Vespa vulgaris (larva) 
Aug. 12 
i 
72-7 
75-8 
31 
56 
Nearly full grown; very active. 
3 
12 
i 
72-7 
74- 
1-3 
52 
Full grown. 
4 
12 
i 
72-7 
75-2 
2-5 
52 
Full grown. 
5 
50 
64-5 
66-5 
2-0 
Larva nearlv full mown : verv active. 
3 
6 
64-7 
66- 
1-3 
*' ° f * 
7 
6 
66-3 
66-8 
0-5 
Larva inactive. 
8 
9 
Athalia (larvre) 
6 
6 
200 
50 
05-3 
65-3 
67-3 
67-3 
2- 
2- 
1- Full grown ; active. 
10 
Melolontha vulgaris (larva) 
Oct. 7 
1 
61-5 
59-7 
60-2 
0-5 
No. 1. 
* 
11 
Melolontha vulgaris (larva) 
7 
1 
61-5 
59-7 
60-3 
0-6 
No. 2. 
Full grown larva;; the temperature 
12 
Melolontha vulgaris (larva) 
8 
1 
64-7 
64-6 
64-7 
01 
No. 1. 
taken while lying in their cells 
13 
Melolontha vulgaris (larva) 
8 
1 
64-7 
64-6 
64-8 
0-2 
No. 2.1 
and compared with the tempera- 
14 
Melolontha vulgaris (larva) 
12 
1 
63-5 
63-5 
63-7 
0-2 
No. 1. 
ture of the soil. 
15 
Melolontha vulgaris (larva) 
12 
1 
63-5 
63-5 
63-7 
0-2 
No. 2. 
