FOOD OF INSECTS. 243 



inner leg. But it knows that it is the sand in the interior of the circle only 

 that is to be excavated, and it therefore constantly uses the leg next the 

 centre. It will readily occur, however^ that to use one leg as a shovel 

 exclusively throughout the whole of such a toilsome operation, would be 

 extremely wearisome and painful. For this difficulty our ingenious pioneer 

 has a resource. After fiiiisliing the excavation of one circular furrow, it 

 traces the next in an opposite direction ; and thus alternately exercises 

 each of its legs without tiring either. 



In the course of its labours it frequently meets with small stones : these 

 it places upon its head one by one, and jerks over the margin of the pit. 

 But sometimes, when near the bottom, a pebble presents itself of a size so 

 large that this process is impossiide, its head not being sufficiently broad 

 and strong to bear so great a weight, and the height being too considerable 

 to admit of projecting so large a body to the top. A more impatient 

 labourer would despair, but not so our insect. A new plan is adopted. 

 By a manoeuvre, not easily described, it lifts the stone upon its back, keeps 

 it in a steady position by an alternate motion of the segments which com- 

 pose that part ; and carefully walking up the ascent with the burthen, 

 deposits it on the outside of the margin. When, as occasionally happons, 

 the stone is round, the labour becomes most difficult and painful. A 

 spectator watching the motions of the ant-lion feels an inexpressible 

 interest in its behalf. He sees it with vast exertion elevate the stone, and 

 begin its arduous retrograde ascent : at every moment the burthen totters 

 to one side or the other : the adroit porter lifts up the segments of its back 

 to balance it, and has already nearly reached the top of tiie pit, when a 

 stumble or a jolt mocks all its efforts, and the stone tumbles headlong to 

 the bottom. Mortified, but not despairing, the ant-lion returns to the 

 charge ; again replaces the stone on its back ; again ascends the side, and 

 artfully avails himself, for a road, of the channel formed by the falling 

 stone, against the sides of which he can support his load. This time pos- 

 sibly he succeeds ; or it may be, iis is often the case, the stone again rolls 

 down. When thus unfortunate, our little Sisyphus has been seen s/.r times 

 patiently to renew his attempt, and was at last, as such heroic resolution 

 deserved, successful. It is only after a series of trials have demonstrated 

 the impossibility of succeeding that our engineer yields to fate, and, quit- 

 ting his half-excavated pit, begins the formation of another. 



When all obstacles are overcome, and the pit is finished, it presents 

 itself as a conical hole rather more than two inches deep, gradually con- 

 tracting to a point at the bottom, and about three inches wide at the top.^ 

 The ant-lion now takes its station at the bottom of the pit, and, that its 

 gruff" appearance may not scare the passengers which approach its den, 

 covers itself with sand all except the points of its expanded forceps. It is 

 not long before an ant on its travels, fearing no harm, steps upon the margin 

 of the pit, either accidentally or for the purpose of exploring the depth 

 below. Alas ! its curiosity is dearly gratified. The faithless sand slides 

 from under its feet ; its struggles but hasten its descent ; and it is pre- 



1 The nests of this animal which I saw at Fontainebleau (in the pit producing the 

 fossil named after that place) were scarcely half the dimensions here given, but 

 thej' might probably be younger insects. I kept one in a box of sand several days, 

 in which it regularly formed its pit, whenever obliterated bj^ shaking. The bottom 

 of the box unfortunately came out as I was upon my return to England, and the 

 animal was killed. 



a 2 



