The Ant-Lion and its Trap (continued
page 2)
by John J. Ward F.E.S.
abdomen in the sand, in this manner obtaining greater power for its
next movement.
 
Top and bottom view of an antlion
Then by means of its fore-leg nearest the centre
of the circle, it loads its broad, flat head with sand, which it
suddenly hurls outside the circle in an
astonishing manner. So it pushes backwards round and round inside the ring,
continually throwing out the sand as it travels. When a circle is completed,
it changes its position and excavates the next furrow in the opposite direction,
thus working its legs on each side alternately, but always loading its head
with sand by means of the inside fore-leg.
Small stones are frequently a source of trouble during the excavation,
and if one is too large to throw out the larva gets beneath it,
lifting it on its back, and adroitly balancing it while it climbs
the side of the pit and until it can deposit it on the outside.
In due course, after many decreasing circles have been excavated,
a conical pit is formed, and at the bottom of this the energetic
grub proceeds to bury itself all but the end of its mandibles,
which are allowed to project.
The ant-lion's pitfall shown in section with the
insect buried in the sand at the bottom In this manner it patiently awaits the approach of an unsuspecting
or inquisitive ant. The larva can endure long fasts, but sooner
or later its patience is rewarded. An ant, while seeking out new
feeding-grounds, meets with this smooth pit and its strange central
object, and never having seen anything like it before (for an ant
usually pays but one visit to the ant-lion's pit), its curiosity
is aroused - it may mean food ! At all events, the naturally inquisitive
ant desires to know, and so it proceeds warily to investigate. Continued...
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