This amounts to saying that, with the Languedocian Sphex, the difficulties of observation increase. No long-meditated experiment is possible in her case; nor, when the first attempts have failed, can one hope to try them again, on the same occasion, with a second or a third subject and so on. If you prepare the materials for your observation in advance, if, for instance, you have in reserve a piece of game which you propose to substitute for that of the Sphex, it is to be feared, nay, it is almost certain that the huntress will not appear; and, when she does come at last, your materials are no longer fit for use and everything has to be improvised in a hurry, that very moment, under conditions that are not always satisfactory. Let us take heart. The site is a first-rate one. Many a time already I have surprised the Sphex here, sunning herself on a vine-leaf. The insect, spread out flat, is basking voluptuously in the heat and light. From time to time it has a sort of frenzied outburst of pleasure: it quivers with content; it rapidly taps its feet on its couch, producing a tattoo not unlike that of rain falling heavily on the leaf. The joyous thrum can be heard several feet away. Then immobility begins again, soon followed by a fresh nervous commotion and by the whirling of the tarsi, a symbol of supreme felicity. I have known some of these passionate sun-lovers suddenly to leave the work-yard, when the larva’s cave has been half-dug, and go to the nearest vine to take a bath of heat and light, after which they would come back to the burrow, as though reluctantly, just to give a perfunctory sweep and soon end by knocking off work, unable to resist the exquisite temptation of luxuriating on the vine-leaves. It may be that the voluptuous couch is also an observatory, whence the Wasp surveys the surrounding country in order to discover and select her prey. Her exclusive game is the Ephippiger of the Vine, scattered here and there on the branches or on any brambles hard by. The joint is a substantial one, especially as the Sphex favours solely the females, whose bellies are swollen with a mighty cluster of eggs.