THE CABINET OF NATURAL HISTORY, 
8 
their escape. When the pitfall is intended to be small, 
it only thrusts its body backwards into the sand as far as it 
can, throwing out at intervals the particles which fall in 
upon it, till it is rendered of the requisite depth. 
By shutting up one of these grubs in a box with loose 
sand, it has been repeatedly observed constructing its trap of 
various dimensions, from one to three inches in diameter, 
according to circumstances. When it intends to make one 
of considerable diameter, it proceeds as methodically as the 
most skilful architect or engineer amongst ourselves. It 
first examines the nature of the soil, whether it be suffi- 
ciently dry and fine for its purpose, and if so, it begins by 
tracing out a circle, where the mouth of its funnel-trap is 
intended to be. Having thus marked the limits of its pit, 
it proceeds to scoop out the interior. Getting within the 
circle, and using one of its legs as a shovel, it places there- 
with a load of sand on the flat part of its head, and it 
throws the whole with a jerk some inches beyond the 
circle. It is worthy of remark that it only uses one leg 
in this operation — the one, namely, which is nearest the 
centre of the circle. Were it to employ the others in 
digging away the sand, it would encroach upon the regu- 
larity of its plan. Working with great industry and 
adroitness in the manner we have just described, it quickly 
makes the round of its circle, and as it works backwards 
it soon arrives at the point where it had commenced. 
Instead, however, of proceeding from this point in the same 
direction as before, it wheels about and works around in 
the contrary direction, and in this way it avoids throwing 
all the fatigue of the labour on one leg, alternating them 
every round of the circle. 
Were there nothing to scoop out but sand or loose earth, 
the little engineer would have only to repeat the opera- 
tions we have described, till it had completed the whole. 
But it frequently happens in the course of its labours, 
sometimes even when they are near a close, that it will 
meet with a stone of some size which would, if suffered to 
remain, injure materially the perfection of its trap. But 
such obstacles as this do not prevent the insect from pro- 
ceeding : on the contrary, it redoubles its assiduity to 
remove the obstruction, as M. Bonnet repeatedly wit- 
nessed. If the stone be small, it can manage to jerk it 
out in the same manner as the sand; but when it is two 
or three times larger and heavier than its own body, it 
must have recourse to other means of removal. The larger 
stone it usually leaves till the last, and when it has removed 
all the sand which it intends, it then proceeds to try what 
it can do with the less manageable obstacles. For this 
purpose, it crawls backwards to the place where a stone 
may be, and thrusting its tail under it, is at great pains 
to get it properly balanced on its back, by an alternate 
motion of the rings composing its body. When it has 
succeeded in adjusting the stone, it crawls up the side of 
the pit with great care and deposits its burden on the 
outside of the circle. Should the stone happen to be 
round, the balance can be kept only with the greatest 
difficulty, as it has to travel with its load upon a slope of 
loose sand which is ready to give way at every step; and 
often when the insect has carried it to the very brink, it 
rolls off its back and tumbles down to the bottom of the 
pit. This accident, so far from discouraging the Ant-lion, 
only stimulates it to more persevering efforts. Bonnet 
observed it renew these attempts to dislodge a stone, five 
or six times. It is only when it finds it utterly impossible 
to succeed, that it abandons the design and commences 
another pit in a fresh situation. When it succeeds in 
getting a stone beyond the line of its circle, it is not con- 
tented with letting it rest there; but to prevent it from again 
rolling in, it goes on to push it to a considerable distance. 
The pitfall, when finished, is usually about three inches 
in diameter at the top, about two inches deep, and gradually 
contracting into a point in the manner of a cone or funnel. 
In the bottom of this pit the Ant-lion stations itself to 
watch for its pray. Should an ant or any other insect 
wander within the verge of this funnel, it can scarcely fail 
to dislodge and roll down some particles of sand, which will 
give notice to the Ant-lion below to be on the alert. In 
order to secure the prey, Reaumur, Bonnet, and others | 
have observed the ingenious insect throw up showers of 
sand by jerking it from its head in quick succession, till the 
luckless ant is precipitated within reach of the jaws of its 
concealed enemy. It feeds only on the blood or juice of 
insects; and as soon as it has extracted these, it tosses the j 
dry carcase out of its den. Its next care is to mount the 
sides of the pitfall and repair any damage it may have j 
suffered; and when this is accomplished, it again buries i 
itself among the sand at the bottom, leaving nothing but its i 
jaws above the surface, ready to seize the next victim. 
When it is about to change into a pupa, it proceeds in 
nearly the same manner as the caterpillar of the water- 
betony moth ( Cucullia scrophularise ). It first builds a 
case of sand, the particles of which are secured by threads 
of silk, and then tapestries the whole with a silken web. * j 
Within this it undergoes its transformation into a pupa, and 
in due time, it emerges in form of a four-winged fly, j 
closely resembling the dragon-flies ( Libellulse ,) vulgarly I 
and erroneously called horse stingers. 
The instance of the Ant-lion naturally leads us to con- 
sider the design of the Author of Nature in so nicely j 
adjusting, in all animals, the means of destruction and of 
escape. As the larger quadrupeds of prey are provided j 
with a most ingenious machinery for preying on the t 
