INTERNAL ANATOMY OF INSECTS. 193 
motion, and insensible of his approach and their own 
danger. ‘Thus it was that I captured that rare insect the 
lobster-moth (Stauropus Fagz) in the New Forest. Some, 
however, have asserted that the caterpillar of the silk- 
worm, except when they moult, never intermits feeding 
day or night, and consequently does not sleep: but the 
accuracy of this statement, both from analogy and obser- 
vation, admits of great doubt. Malpighi informs us that 
these caterpillars for an hour and more, twice a day, re- 
main immoyeable with their heads bent down as though 
asleep, and even if disturbed, resume again the same 
inactive posture?; and other larve in great numbers 
certainly seem to have regular intermissions from eating 
of considerable duration: those called Geometers, for 
hours together remain motionless projected from a twig, 
to which they adhere by their posterior prolegs alone ; 
and the processionary caterpillars make only nzghtly 
sorties from their nests, passing the day im inaction and 
repose’. Bees have been often seen by Huber, when 
apparently wearied with exertion, even in the middle of 
the day to insert the half of their bodies into an empty 
cell, and remain there, as if taking a nap, without mo- 
tion for half an hour or longer‘; and at night they regu- 
larly muster in a state of sleep-like silence. Instances of 
other bees that appear to sleep have before been mention- 
ed¢’. Mr. Brightwell once observed an individual living 
specimen of Haltica concinna, which appeared to remain 
motionless on the same spot of a wall for three successive 
days. 
* De Bombyc. 5. > Reaum. ii. 185—, 
© Von. lp. 189, d@ Jbid. p. 282, 
VOL. IV. a 
