The disproportion in the sizes of the predatory wasps and their insect prey is indeed astonishing. The great sand-hornet selects for its most frequent victim the buzzing cicada, or harvest-fly, an insect much larger than itself, and which it carries off to its long sand tunnels by short flights from successive elevated points, such as the limbs of trees and summits of rocks, to which it repeatedly lugs its clumsy prey. In the present instance the contrast between the slight body of the wasp and the plump dimensions of the caterpillar was even more marked, and I determined to ascertain the proportionate weight of victor and victim. Constructing a tiny pair of balances with a dead grass stalk, thread, and two disks of paper, I weighed the wasp, using small square pieces of paper of equal size as my weights. I found that the wasp exactly balanced four of the pieces. Removing the wasp and substituting the caterpillar, I proceeded to add piece after piece of the paper squares until I had reached a total of twenty-eight, or seven times the number required by the wasp, before the scales balanced. Similar experiments with the tiny black wasp and its spider victim showed precisely the same proportion, and the ratio was once increased eight to one in the instance of another species of slender orange-and-black-bodied digger which I subsequently found tugging its caterpillar prey upon my door-step patch.
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The peculiar feature of the piling of stones above the completed burrow was not a mere individual accomplishment of my wire-waisted wasp. On several occasions since I have observed the same manoeuvre, which is doubtless the regular procedure with this and other species. The smaller orange-spotted wasp just alluded to indicated to me the location of her den by pausing suggestively in front of a tiny cairn. In this instance a small flat stone, considerably larger than the tunnel, had been laid over the opening, and the others piled upon it. On two occasions I have surprised this same species of wasp industriously engaged in the selection of a suitable flat foundation-stone with which to cover her burrow: her widely extended slender jaws enable her to grasp a pebble nearly a third of an inch in width.
In my opening vignette I have indicated two other door-step neighbors which bore my industrious wasps company in their arena of one square yard. To the left, surrounding a grass stem, will be seen an object which is unpleasantly familiar to most country folks-that salivary mass variously known by the libellous names of "snake-spit," "cow-spit," "cuckoo-spit," "toad-spit," and "sheep-spit," or the inelegant though expressive substitute of "gobs." The foam-bath pavilion of the "spume-bearer," with his glittering, bubbly domicile of suds, is certainly familiar to most of my readers; but comparatively few, I find, have cared to investigate the mysterious mass, or to learn the identity of the proprietor of the foamy lavatory.
The common name of "cow-spit," with the implied indignity to our "rural divinity," becomes singularly ludicrous when we observe not only the frequent generous display of the suds samples, thousands upon thousands in a single small meadow, but the further fact that each mass is so exactly landed upon the central stalk of grass or other plant-"spitted" through its centre, as it were. The true expectorator is within, laved in his own home-made suds. If we care to blow or scrape off the bubbles, we readily disclose him--a green speckled bug, about a third of an inch in length in larger specimens, with prominent black eyes, and blunt, wedge-shaped body.
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In the appended sketch I have indicated two views of him, back and profile, creeping upon a grass stalk. A glance at the insect tells the entomologist just where to place him, as he is plainly allied to the cicadæ, and thus belongs to the order
This is the spume-bearer,
