THE ANT-LION. 



473 



Within this first furrow it digs a second, then 

 a third, and afterwards others, which are al- 

 ways less than the preceding. Then it begins 

 to deepen its hole, sinking lower and lower 

 into the sand, which it throws with its horns 

 and feelers towards the edges, as we see men 

 throw up sand in a gravel-pit. Thus, by re- 

 peating its labours all round, the sand is thrown 

 up in a circle about the edge of the pit, until 

 the whole is quite completed. This hole is 

 always formed in a perfect circle ; and the pit 

 itself resembles the inside of an inverted fun- 

 nel. 1 When this insect first leaves the egg 



1 The Ant- Lion. The observations of the continental 

 naturalists have made known to us a pitfall constructed 

 by an insect, the details of whose operations are exceed- 

 ingly curious we refer to the grub of the ant-lion 

 (Myrmeleonformicarius), which, though marked by Dr 

 Turton and Mr Stewart as British, has not (at least of 

 late years) been found in this country. As it is not, 

 however, uncommon in France and Switzerland, it is 

 probable it may yet be discovered in some spot hitherto 

 unexplored. 



The ant-lion grub being of a gray colour, and having 

 its body composed of rings, is not unlike a wood-louse 

 (Oniscus), though it is larger, more triangular, has only 

 six legs, and most formidable jaws, in form of a reaping- 

 hook, or a pair of calliper compasses. These jaws, how- 

 ever, are not for masticating, but are perforated and tu- 

 bular, for the purpose of sucking the juices of ants upon 

 which it feeds. Vallisnieri was, therefore, mistaken, as 

 Reaumur well remarks, when he supposed that he had 

 discovered its mouth. Its habits require that it should 

 walk backwards, and this is the only species of locomotion 

 it can perform. Even this sort of motion it exe- 



of the Ant-Lion magnified, with one perfect Trap, 



and another begun. 



cutes very slowly ; and were it not for the ingenuity oi 

 its stratagems, it would fare but sparingly, since its chiel 

 iood consists of ants, whose activity and swiftness of foot 

 would otherwise render it impossible for it to make asin- 



VOL. II. 



and is newly hatched, the first pit it makes is 

 very small ; but as it grows bigger, it makes 

 a larger hole ; which is destined, like a pit- 

 fall, to entrap its prey. It is generally about 

 two inches deep, and as much in diameter. 



gle capture. Nature, however, in this, as in nearly every 

 other case, has given a compensating power to the indi- 

 vidual animal, to balance its privations. The ant-lion is 

 slow- but it is extremely sagacious ; it cannot follow 

 its prey, but it can entrap it. 



The snare which the grub of the ant-lion employs, con- 

 sists of a funnel-shaped excavation formed in loose sand, 

 at the bottom of which it lies in wait for the ants that 

 chance to stumble over the margin, and cannot, from the 

 looseness of the walls, gain a sufficient footing to effect 

 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 me- 

 thodically as the most skilful architect or engineer 

 amongst ourselves. It first examines the nature of the 

 soil, whether it be sufficiently dry and fine for its pur- 

 pose, 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 therewith 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 re- 

 mark 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 regularity 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 be- 

 fore, it wheels about and works a round in the contrary 

 direction, and in this way it avoids throwing all the fa- 

 tigue 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 

 operations 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 in- 

 sect from proceeding : on the contrary, it redoubles its 

 assiduity to remove the obstruction, as M. Bonnet re- 

 peatedly witnessed. If the stone be small, it can man- 

 age 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 re- 

 moval. The larger stones 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 ma. 

 riageable obstacles. For this purpose, it crawls back- 

 wards to the place where a stone may be, and thrusting 

 its tail under it, is at great pains to get it properly ba- 

 lanced 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 upou a slope of loose sand which is ready to 

 3o 



