


26 THE INSECT WORLD. 
Oryctes nasicornis, four times only. The bee can draw twenty 
times the weight of its body ; Donacia nymphea,* forty-two times 
its own weight. 
From this it follows that if the horse possessed the same 
strength as this last insect, or if the insect were the size of a horse, 
they would either of them be able to draw 155,250 lbs. M. 
Plateau has ascertained the pushing power in insects, by introducing 
them into a pasteboard tube, the interior of which was made rough, 
and in which was fixed a glass plate, which allowed the lght 
to penetrate into the prison. The animal, if excited, struggled 
with all its strength against the transparent plate, which, on being 
pushed forward, turned a lever adapted to a miniature dynamo- 
meter, which indicated the amount of effort exercised. 
The results thus obtained prove that the pushing power, lke 
the power of traction, is greater in inverse proportion to the 
size and weight of the animal. A few figures will better explain 
this curious law. In Oryctes nasicornis, the proportion of the 
pushing power to the weight of the insect is only three to two ; 
in Geotrupes stercorarius, it is sixteen to two; and in Onthophagus 
nuchicornis, seventy-nine to six. 
Experiments have been made on the lifting power of insects, 
by fastening a ball of soft wax to a thread attached to the hind 
legs. The proportion of the weight lifted has been found equal 
to that of the body. That is to say, that the insect when flying 
can lift its own weight. This is proved by the following calcula- 
tions :—In the Neuroptera the proportion is 1,in the Dragon-fiy 
(Libellula vulgaia), ‘7 in Lestes sponsa. In the order Hymen- 
optera, it is "738 in the bee, and -63 in Bombus terrestris, the 
humble bee. In the Diptera itis ‘9 in Calliphora vomitoria,t 1:84 
in the Syrphus corolle, and 1°77 in the house-fly. 
These results show that insects have only sufficient power to 
sustain their own weight when flying, as the above calculations 
exhibit the maximum of which they are capable, and at the utmost 
this strength would only compensate for the fatigue occasioned 
by the action of flight. 
At the same time it is to be observed that the Diptera, and . 
among others the house-fly, can sustain their flight longer than the 
* A beetle.—Ep. t The meat-fly.—Eb. 
