318 
MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 
Table XI. 
Period of observa- 
tion. 
No. 
Age of the Insects. 
Atmo- 
sphere. 
Insect. 
Differ- 
ence. 
Pulse. 
July 31,1834. 
1 
Three davs in last skin, feeding 
0 
71-2 
0 
72-3 
fi 
54 
2 
Three days in last skin, resting 
71-2 
72-2 
1 
49 
3 
Five days in last skin, feeding 
71-2 
72-2 
1 
49 
4 
Five days in last skin, feeding 
71-6 
72-6 
1 
50 
5 
Seven days in last skin; has been long sleeping ... 
71-2 
71-6 
•4 
29 
6 
Seven days in last skin ; aroused and active 
71-6 
72-4 
•8 
38 
The same general accordance which exists in the larva between the quantity of 
respiration, amount of heat developed, and number of pulsations, exists also in the 
perfect insect. In order to observe the number of pulsations in the perfect insect it 
is necessary to denude the dorsal surface of the abdomen of its thick covering of 
scales, and when this has been done completely the pulsation of the vessel is readily 
observed. In a male specimen of Sphinx ligustri which had been exerting itself in 
active flight for several minutes around my sitting-room, I found the number of pul- 
sations was 127 per minute, while the insect then had a temperature of 9° Fahr. above 
that of the atmosphere, which was 70° Fahr. On the following day, after it had been 
exerting itself in a similar manner for a much longer space of time, the temperature 
of the atmosphere being 69 0, 5, the number of its pulsations was then 139, and its 
number of respirations forty-two per minute, but its amount of heat was only 5 0, 5 Fahr. 
When it had remained at rest about half an hour its temperature was only °-5, while the 
number of its respirations was eighteen, and of its pulsations forty-nine ; and at the 
expiration of three quarters of an hour, when it was perfectly quiet and apparently 
asleep, its temperature was only 0- 2, its number of respirations fifteen, and its pulse 
forty-two. In these instances the accordance between the number of respirations 
and pulsations, and the temperature of the insect was nearly uniform, but in some of 
the other observations the same uniformity between the amount of heat developed 
and the number of pulsations is not so strictly observed. Thus in No. 12, Table V., 
the temperature of the insect after violent exertion was 9° Fahr., the number of pulsa- 
tions 127, while in No. 14 the temperature was only 4 0, 6, but the pulsations amounted 
to 151 ; and in No. 15 the temperature was 4 0, 3, but the pulsations only 110. 
It is thus evident that in the perfect insect, as in the larva, there are sometimes 
similar irregularities in the rate, or velocity of pulsation, and which irregularities 
when compared with each other do not appear to have relation to the quantity of 
heat developed, while the general, or what appears to be the average rate of pulsa- 
tion, is in almost uniform accordance with the amount of heat and number of respi- 
rations. But these apparent discrepancies may, perhaps, be explained by the circum- 
stance, that when the pulsations are excessive in number they are small, rapid, and 
intermittent, like the pulsation in certain excited states in the human body, and this 
is the case in every instance of excessive pulsation, both in the larva and perfect in- 
sect ; while in those instances in which there is a near accordance between the rate 
of pulsation, amount of heat developed, and number of respirations, the pulsatory 
motions are full, regular, and without intermissions, so that the relative quantity of 
