This wasp was much larger than the one just described, being about an inch in length. Its wings were pale brown and its body jet-black, with sundry small yellowish spots about the thorax. But its most conspicuous feature, and one which would ever fix the identity of the creature, was the long, slender, wire-like waist, occupying a quarter of the length of its entire body.
In a moment or two the wasp had returned, and stood at the mouth of the shallow pit. Eying me intently for a space, and satisfied that there was nothing to fear, she dived into the hollow and began to excavate, turning round and round as she gnawed the earth at the bottom, and shovelling it out with her spiked legs. Now and then she would back out of the burrow to reconnoitre, and her alert attitude at such times was very amusing-her antennæ drooping towards the burrow and in incessant motion; the abdomen on its long wire stem bobbing up and down at regular intervals, accompanied by a flipping motion of the wings; the short fore legs, one or both, upraised with comical effect.
[Illustration]
As the tunnel was deepened a new method of excavation was employed. It has now reached a depth of an inch, only the extremity of the insect's body appearing, and the two hindermost legs clinging to surrounding earth for purchase. The deep digging is now accompanied by a continual buzzing noise, resembling that produced by a bluebottle fly held captive between one's fingers. At intervals of about ten or fifteen seconds the wasp would quickly back out of the burrow, bringing a load of sand, which it held between the back of the jaws and its thorax, sustained at the sides by the two upraised fore legs. After a moment's pause with this burden, the insect would make a sudden short darting flight of a foot or more in a quick circuit, hurling the sand a yard or more distant from the burrow. At the end of about fifteen minutes the burrow was sunk to the depth of an inch and a half, the wasp entirely disappearing, and indicated only by the continuous buzzing.
At this time, the luncheon hour having arrived, I was obliged to pause in my investigations, and in order to be able to locate the burrow in the event of its obliteration by the wasp before my return, I scratched a circle in the hard dirt, the hole being at its exact centre.
[Illustration]
Upon my return, an hour later, I was met with a surprise. The ways of the digger-wasps of various species were familiar, but I now noted a feature of wasp-engineering which indeed seems to await its chronicler, as I find no mention of it by the wasp-historians.
At the exact centre of my circle, in place of a cavity, I now found a tiny pile of stones, supported upon a small stick and fragment of leaf, which had been first drawn across the opening.
This was evidently a mere temporary protection of the burrow, I reasoned, while the digger had departed in search of prey, and my surmise was soon proved to be correct, as I observed the wasp, with bobbing abdomen and flipping wings, zigzagging about the vicinity. Presently disappearing beneath a small plantain leaf, she quickly emerged, drawing behind her not a spider, as in the case of her smaller predecessor, but a big green caterpillar, nearly double her own length, and as large around as a slate-pencil-a peculiar, pungent, waspy-scented species of "puss-moth" larva, which is found on the elm, and with which I chanced to be familiar.
The victim being now ready for burial, the wasp sexton proceeded to open the tomb. Seizing one stone after another in her widely opened jaws, they were scattered right and left, when, with apparent ease and prompt despatch, the listless larva was drawn towards the burrow, into whose depths he soon disappeared. Then, after a short and suggestive interval, followed the emergence of the wasp, and the prompt filling in of the requisite earth to level the cavity, much as already described, after which the wasp took wing and disappeared, presumably bent upon a repetition of the performance elsewhere. But she had not simply buried this caterpillar victim, nor was the caterpillar dead, for these wasp cemeteries are, in truth, living tombs, whose apparently dead inmates are simply sleeping, narcotized by the venom of the wasp sting, and thus designed to afford fresh living food for the young wasp grub, into whose voracious care they are committed.
By inserting my knife-blade deep into the soil in the neighborhood of this burrow I readily unearthed the buried caterpillar, and disclosed the ominous egg of the wasp firmly imbedded in its body. The hungry larva which hatches from this egg soon reaches maturity upon the all-sufficient food thus stored, and before many weeks is transformed to the full-fledged, long-waisted wasp like its parent.
