MEANS OF DEFENCE OF INSECTS. 415 
Malachius endeavour to alarm their enemies and show their rage by puff- 
ing out and inflating four vesicles from the sides of their body, which are of 
a bright red, soft, and of an irregulav shape. When the cause of alarm is 
removed, they are retracted, so that only a small portion of them ap- 
ears. 
Insects often endeavour to repel or escape from assailants by their motions, 
Mr. White, mentioning a wild bee that makes its nest on the summit of 
a remarkable hill neat Lewes in Sussex, in the chalky soil, says:— ‘‘ When 
people approach the place these insects begin to be alarmed, and with a 
sharp and hostile sound dash and strike round the heads and faces of in~ 
truders. I have often been interrupted myself while contemplating the 
grandeur of the scenery around me, and have thought myself in danger of 
being stung.” *—'The hive-bee will sometimes have recourse to the same 
expedient, when her hive is approached too near, and thus give you notice 
what you may expect if you do not take her warning and retire.— 
Humble-bees when disturbed, whether out of the nest or in it, assume 
some very grotesque and at the same time threatening attitudes. If you 
ut your finger to them, they will either successively or simultaneously 
ift up the three legs of one side; tirn themselves upon their back; bend 
up their anus and show their sting accompanied by a drop of poison. Some- 
times they willl even spirt out that liquor. When in the nest, if it be at- 
tacked, they also beat their wings violently and emit a great hum.® 
These motions menace vengeance; those of some other insects are 
merely to effect their escape. Thus I have observed that the species of 
the May-fly tribe ('richoptera*), when I have attempted to take them, have 
often glided away from under my hand — without moving their limbs that 
Tcould discover —in a remarkable manner.’ M. de Villiers informs us 
that different species of moths of the genera Orthosia and Cerastis never 
avail themselves of their wings to escape the dangers which threaten them ; 
but if you attempt to seize them immediately let themselves fall to the ground, 
and then begin running with such rapidity, that it is very difficult to obtain 
possession of them.® And in like manner various Curculionide and other cole- 
opterous insects, if they see any one approach, contract their legs, and suffer 
themselves to fall from the leaf or other surface on which they rest,among the 
grass or plants below, and thus escape, To notice the ordinary motions of 
insects, which are often means by which they avoid danger, would here be 
premature, since they will be fully considered in a subsequent letter. I 
shall, therefore, only mention the zigzag flight of butterflies and the traverse 
sailing of humble-bees, which certainly render it more difficult for the birds 
to catch them while on the wing. 
Noises are another means of defence to which insects have occasional 
recourse. I have heard the lunar dung-beetle (Copris /unaris), when dis- 
turbed, utter a shrill sound. Dynastes Oromedon, another of the lamel- 
licorn insects, was observed by Dr. Arnold to make, when alarmed, a kind 
of creaking noise, which it produced by rubbing its abdomen against its 
elytra, A third of the same tribe (Zrow sabulosus) emits a small sibilant or 
chirping noise, as I once observed when I found several feeding in a ram’s 
} De Geer, iv. 74, 2 Nat. Hist. ii. 268. 
5 P. Huber, in Linn. Trans, vi. 219. Kirby, Mon. Ap. Angl. i. 201. 
Kirby in Linn. Trans. xi, 87. note *. 
Evidently by the action of the numerous spines on the legs all directed back- 
wards, just as an ear of barley will mount up the sleeve of a coat. 
Ann, Soc. Ent. de France, xi, bull, xii, 
