room again where I pored over differentials and integrals, where I calmed my poor burning head by gazing at Mont Ventoux, whose summit held in store for my coming expedition' those denizens of arctic climes, the saxifrage and the poppy! And to see my familiar friend, the blackboard which I hired at five francs a year from a crusty joiner, that board whose value I paid many times over, though I. could never buy it outright, for want of the necessary cash! The conic sections which I described on that blackboard, the learned hieroglyphics!
Though all my efforts, which were the more deserving because I had to work alone, led to almost nothing in that congenial calling, I would begin it all over again if I could. I should love to be conversing for the first time with Leibnitz and Newton, with Laplace and Lagrange, with Cuvier and Jussieu, even if I had afterwards to solve that other arduous problem: how to procure one's daily bread. Ah, young men, my successors, what an easy time you have of it today! If you don't know it, then let me tell you so by means of these few pages from the life of one of your elders.
But let us not forget our insects, while listening to the echoes of illusions and difficulties roused in my memories by the cupboard window and the hired blackboard. Let us go back to the sunken roads of the Legue, which have become classic, so they say, since the appearance of my notes on the Oil beetles. Ye illustrious ravines, with your sun-baked slopes, if I have contributed a little to your fame, you, in your turn, have given me many fair hours of forgetfulness in the happiness of learning. You, at least, did not lure me with vain hopes; all that you promised you gave me and often a hundredfold. You are my promised land, where I would have sought at the last to pitch my observer's tent. My wish was not to be realized. Let me, at least, in passing, greet my beloved animals of the old days.
I raise my hat to Cerceris tuberculata, whom I see engaged on that slant, storing her Cleonus [a large species of weevil]. As I saw her then, so I see her now: the same staggering attempts to hoist the prey to the mouth of the burrow; the same brawls between males watching in the brushwood of the kermes oak. The sight of them sends a younger blood coursing through my veins; I receive as it were the breath of a new springtime of life. Time presses; let us pass on.
Another bow on this side. I hear buzzing up above, on that ledge, a colony of Sphex wasps, stabbing their crickets. We will give them a friendly glance, but no more. My acquaintances here are too numerous; I have not the leisure to renew my former relations with all of them. Without stopping, a wave of the hat to the Philanthi [bee-hunting wasps] who send the long avalanches of rubbish streaming down from their nests; and to Stizus ruficornis, [a hunting wasp] who stacks her praying mantises between two flakes of sandstone; and to the silky Ammophila [a digger wasp] with the red legs, who collects an underground store of loopers [also known as measuring worms, the larvae or caterpillars of the geometrid moth] and to the Tachtyti [hunting wasps], devourers of locusts; and to the Eumenes, builders of clay cupolas on a bough.
Here we are at last. This high, perpendicular rock, facing the south to a length of some hundreds of yards and riddled with holes like a monstrous sponge, is the time-honored dwelling place of the hairy-footed Anthophora and of her rent free tenant, the three-horned Osmia. Here also swarm their exterminators: the Sitaris beetle, the parasite of the Anthophora; the Anthrax fly, the murderer of the Osmia. Ill informed as to the proper period, I have come rather late, on the 10th of September. I should have been here a month ago, or even by the end of July, to watch the fly's operations. My journey threatens to be fruitless: I see but a few rare Anthrax flies, hovering round the face of the cliff. We will not despair, however, and we will begin by consulting the locality.
The Anthophora's cells contain this bee in the larval stage. Some of them provide me with the oil beetle and the Sitaris, rare finds at one time, today of no use to me. Others contain the Melecta [a parasitic bee] in the form of a highly colored pupa, or even in that of the full grown insect. The Osmia, still more precocious, though dating from the same period, shows herself exclusively in the adult form, a bad omen for my investigations, for what the Anthrax demands is the larva and not the perfect insect. The fly's grub doubles my apprehensions. Its development is complete, the larva on which it feeds is consumed, perhaps several weeks ago. I no longer doubt but that I have come too late to see what happens in the Osmia's cocoons.
Is the game lost? Not yet. My notes contain evidence of Anthrax flies hatching in the latter half of September. Besides, those whom I now see exploring the rock are not there to take exercise: their preoccupation is the settling of the family. These belated ones cannot tackle the Osmia, who, with her firm, adult flesh, would not suit the nursling's delicate needs and who, moreover, powerful as she is, would offer resistance. But in autumn a less numerous colony of honey gatherers takes the place, upon the slope, of the spring colony, from which it differs in species. In particular, I see the Diadem Anthidium [a clothier bee who lines her nest with wool and cotton] at work, entering her galleries at one time with her harvest of pollen dust and at another with her little bale of cotton. Might not these autumnal Bees be themselves exploited by the Anthrax, the same that selected the Osmia as her victim a couple of months earlier? This would explain the presence of the Anthrax flies whom I now see fussing about.
A little reassured by this conjecture, I take my stand at the foot of the rock, under a broiling sun; and, for half a day, I follow the evolutions of my flies. They flit quietly in front of the slope, at a few inches from the earthy covering. They go from one orifice to the next, but without even penetrating. For that matter, their big wings, extended crosswise even when at rest, would resist their entrance into a gallery, which is too narrow to admit those spreading sails. And so they explore the cliff, going to and fro and up and down, with a flight that is now sudden, now smooth and slow. From time to time, I see the Anthrax quickly approach the wall and lower her abdomen as though to touch the earth with the end of her ovipositor. This proceeding takes no longer than the twinkling of an eye. When it is done, the insect alights elsewhere and rests. Then it resumes its sober flight, its long investigations and its sudden blows with the tip of its belly against the layer of earth. The Bombylii [bee flies] observe similar tactics when soaring at a short height above the ground.
I at once rushed to the spot touched, lens in hand, in the hope of finding the egg which everything told me was laid during that tap of the abdomen. I could distinguish nothing, in spite of the closest attention. It is true that my exhaustion, together with the blinding light and scorching heat, made examination very difficult. Afterwards, when I made the acquaintance of the tiny thing that issues from that egg, my failure no longer surprised me. In the leisure of my study, with my eyes rested and with my most powerful glasses held in a hand no longer shaking with excitement and fatigue, I have the very greatest difficulty in finding the infinitesimal creature, though I know exactly where it lies. Then how could I see the egg, worn out as I was under the sun-baked cliff, how discover the precise spot of a laying performed in a moment by an insect seen only at a distance? In the painful conditions wherein I found myself, failure was inevitable.
Despite my negative attempts, therefore, I remain convinced that the Anthrax flies strew their eggs one by one, on the spots frequented by those bees who suit their grubs. Each of their sudden strokes with the tip of the abdomen represents a laying. They take no precaution to place the germ under cover; for that matter, any such precaution would be rendered impossible by the mother's structure. The egg, that delicate object, is laid roughly in the blazing sun, between grains of sand, in some wrinkle of the calcined chalk. That summary installation is sufficient, provided the coveted larva be near at hand. It is for the young grub now to manage as best it can at its own risk and peril.
Though the sunken roads of the Legue did not tell me all that I wished to know, they at least made it very probable that the coming grub must reach the victualled cell by its own efforts. But the grub which we know, the one that drains the bag of fat which may be a Chalicodoma larva or an Osmia larva, cannot move from its place, still less indulge in journeys of discovery through the thickness of a wall and the web of a cocoon. So an imperative necessity presents itself: there must perforce be an initial larva form, capable of moving and organized for searching, a form under which the grub would attain its end. The Anthrax would thus possess two larval states: one to penetrate to the provisions; the other to consume them. I allow myself to be convinced by the logic of it all; I already see in my mind's eye the wee animal coming out of the egg, endowed with sufficient power of motion not to dread a walk and with sufficient