It is at the end of July that the Yellow-winged Sphex tears the cocoon that has protected her until then and flies out of her subterranean cradle. During the whole of August she is frequently seen flitting, in search of some drop of honey, around the spiked heads of the field eryngo, the commonest of the hardy plants that brave the heat of the dog-days in this month. But this careless life does not last long, for by the beginning of September the Sphex is at her arduous task as a sapper and huntress. She generally selects some small plateau, on the high banks by the side of the roads, wherein to establish her home, provided that she find two indispensable things there: a sandy soil, easy to dig; and sunshine. No other precaution is taken to protect the dwelling against the autumn rains or winter frosts. A horizontal site, unprotected, lashed by the rain and the winds, suits her perfectly, on condition, however, that it is exposed to the sun. And, when a heavy shower comes in the middle of her mining, it is pitiful next day to see the half-built galleries in ruins, choked with sand and finally abandoned by their engineers. The Sphex seldom practises her industry alone; the site selected is usually exploited by small bands of ten or twenty sappers or more. One must have spent days in contemplating one of these villages to form any idea of the restless activity, the spasmodic haste, the abrupt movements of those hard-working miners. The soil is rapidly attacked with the rakes of the forefeet: canis instar, as Linnæus says. No mischievous puppy displays more energy in digging up the ground. At the same time, each worker sings her glad ditty, which consists of a shrill and strident noise, constantly broken off and modulated by the vibrations of the wings and thorax. One would think that they were a troop of merry companions encouraging one another in their work with a cadenced rhythm. Meanwhile the sand flies, falling in a fine dust on their quivering wings; and the too bulky gravel, removed bit by bit, rolls far away from the workyard. If a piece seems too heavy to be moved, the insect gets up steam with a shrill note which reminds one of the woodman’s ‘Hoo!’ Under the redoubled efforts of tarsi and mandibles the cave soon takes shape; the insect is already able to dive into it bodily. We then see a lively alternation of forward movements, to loosen new materials, and backward movements, to sweep the rubbish outside. In this constant hurrying to and fro the Sphex does not walk, she darts as though shot from a spring; she bounds with throbbing abdomen and quivering antennæ, her whole body, in short, animated with a musical vibration. The miner is now out of sight; but we still hear underground her untiring song, while at intervals we catch a glimpse of her hind-legs, pushing a torrent of sand backwards to the mouth of the burrow. From time to time the Sphex interrupts her subterranean