A poor unfortunate green caterpillar, which, with a very little forcible persuasion in the interest of science, was induced to take a short-cut across this nice clean space of earth to the clover beyond, was the next martyr to my passion for original observation. He might have pursued his even course across the arena unharmed, but he too persisted in trespassing, and suddenly was seen to transform from a slow creeping laggard into the liveliest acrobat, as he stood on his head and apparently dived precipitately into the hole which suddenly appeared beneath him. A certain busy fly made itself promiscuous in the neighborhood, more than once to the demoralization of my necessary composure, as it crept persistently upon my nose. What was my delight when I observed the fickle insect in curious contemplation of a pair of calipers at the centre of one of the little courts! But, whether from past experience or innate philosophy in the insect I know not, the pronged hooks, though coming together with a click once or twice at the near proximity of the tempter, failed in their opportunity, and the trap was soon seen carefully set again, flush with the ground at the mouth of the burrow.
The contrast of these clean-swept door-yards with the mound of débris of the ants suggested an investigation of the comparative methods of burrowing and the disposal of the excavated material. Here is a hole evidently some inches in depth; what, then, has become of the earth removed? Suiting action to the thought, I swept into the openings of two or three of the holes quite a quantity of loose earth scraped from the close vicinity, and thus completely obliterated the opening of burrow, door-yard and all.
I awaited in vain any sign of returning activity at the surface, and, my patience being somewhat taxed, I entered my studio, where I remained for a quarter of an hour, perhaps. Upon stealing cautiously to the doorway, I observed all the obliterated holes had reappeared, and upon taking once more my original position I was soon rewarded with a demonstration of the method of excavation. After a moment or two a pellet of earth seemed suddenly to rise from within the cavity, and when arrived at the level of the ground was suddenly shot forth a distance of five or six inches, as though thrown from a tiny round flat shovel, which suddenly flashed from the opening, and as quickly retired to its depths, though not without a momentary display of two curved prongs and a formidable show of spider-like legs.
After a short lapse of time the act was repeated, this time a tiny stone being brought to the surface, and, after a brief pause at the doorway, was jerked to a distance as from a catapult. I now concluded to try the power of this propelling force, and taking a small stone, about three-quarters of an inch in length and a quarter-inch in thickness, laid it over the mouth of the tunnel. A few minutes passed, when I noticed a slight motion in the stone, immediately followed by a forcible ejectment, which threw it nearly an inch, the propelling instrument retiring so quickly into the burrow beneath as to scarce afford a glimpse. The stone appeared almost to have jumped voluntarily.
For an hour or more the bombardment of pellets and small stones continued from the mouth of the pit, until a small pile of the spent ammunition had accumulated at several inches distance, and at length the hole entirely disappeared, the earth in its vicinity presenting an apparently level surface-an armed peace, in truth, with the two touchy curved calipers on duty, as already described.
[Illustration]
Following the hint of past experience, I concluded to explore the depths of one of these tunnels, especially as I desired a specimen of the wily tenant for portraiture; and it is, indeed, an odd fish that one may land on the surface if he be sufficiently alert in his angling. No hook or bait is required in this sort of fishing. Taking a long culm of timothy-grass, I inserted the tip into the burrow. It progressed without impediment two, three, six, eight inches, and when at the depth of about ten inches appeared to touch bottom, which in this kind of angling is the signal for a "strike" and the landing of the game. Instantly withdrawing the grass culm, I found my fish at its tip, from which he quickly dropped to the ground. His singular identity is shown in my illustration-an uncouth nondescript among grubs. His body is whitish and soft, with a huge hump on the lower back armed with two small hooks. His enormous head is now seen to be apparently circular in outline, and we readily see how perfectly it would fill the opening of the burrow like an operculum. But a close examination shows us that this operculum is really composed of two halves, on two separate segments of the body, the segment at the extremity only being the true head, armed with its powerful, sharp, curved jaws. As he lies there sprawling on his six spider-like legs, we may now easily test the skill of his trap, and gain some idea of his voracious personality.
If with the point of our knife-blade, holding it in the direction of the insect's body, we now touch its tail, what a display of vehement acrobatics! Instantly the agile body is bent backward in a loop, while the teeth fasten to the knife-blade with an audible click. If our finger-tip is substituted for the steel, the force of the stroke and the prick and grip of the jaws are unpleasantly perceptible.
In order to fully comprehend the make-up of this curious cave-dweller we must turn biologists for the moment. He must be considered from the evolutionary stand-point, or at least from the stand-point of comparative anatomy.
The first discovery that we make is that as we now see him he is crawling on his back-a fact which seems to have escaped his biographers heretofore. It is, in truth, the underside of his head which is uppermost at the mouth of the burrow, and his six zigzag legs are distorted backward to enable him to keep this contrary position. And what a hideous monster is this, whose flat, metallic, dirt-begrimed face stares skyward from this circular burrow! Well might it strike terror to the heart of the helpless insect which should suddenly find himself confronted by the motionless stare of these four cruel, glistening black eyes! But he is now a "fish out of water," and is about as helpless, nature never having intended him to be seen outside of his burrow-at least, in this present form. There he dwells, setting his circular trap at the mouth of his pitfall, and waiting for the voluntary sacrifice of his insect neighbors to fill his maw.
But this uncouth shape, which so courts obscurity, is not always thus so reasonably retiring. A few glass tumblers inverted above as many of these larger holes during the summer will intercept the winged sprite into which he is shortly to be transfigured-a brilliant metallic-hued beetle, perhaps flashing with bronzy gold or glittering like an emerald-the beautiful cicindela, or tiger-beetle, known to the entomologist as the most agile winged among the coleopterous tribe; known to the populace, perhaps, simply as a bright glittering fly that revels in the hot summer sands of the sea-shore or dusty country road, making its short spans of glittering flight from the very feet of the observer.
[Illustration]
If we capture one of them with our butterfly-net he will be found to bear a general resemblance to the portrait here indicated-a slender-legged, proportionably large-headed beetle, with formidable jaws capable of wide extension, and re-enforced by an insatiate carnivorous hunger inherited from his former estate.
It will thus be seen that all the holes which we observe in the ground are not ant-holes; nor, indeed, are they monopolized by the tiger-beetles. There were other tunnels which I saw dug in my square yard of earth on that morning, which, while not of quite such depth, represented equally deep-laid plans.