Social Life in the Insect World

by Jean-Henri Fabre

Towards the end of March this curious cocoon yielded up a female of the Lesser Peacock, which was immediately sequestered under a wire-gauze cover in my study. I opened the window to allow news of the event to reach the surrounding country, and left it open so that such visitors as presented themselves should find free access to the cage. The captive clung to the wire gauze and did not move for a week.

She was a superb creature, this prisoner of mine, with her suit of brown velvet, crossed by undulating lines. The neck was surrounded by white fur; there was a carmine spot at the extremity of the upper wings, and four great eyes in which were grouped, in concentric crescents, black, white, red, and yellow ochre: almost the colouring of the Great Peacock, but more vivid. Three or four times in my life I had encountered this butterfly, so remarkable for its size and its costume. The cocoon I had recently seen for the first time; the male I had never seen. I only knew that, according to the books, it was half the size of the female, and less vividly coloured, with orange-yellow on the lower wings.

Would he appear, the elegant unknown, with waving plumes; the butterfly I had never yet seen, so rare does the Lesser Peacock seem to be in our country? Would he, in some distant hedge, receive warning of the bride who waited on my study table? I dared to hope it, and I was right. He arrived even sooner than I had hoped.

Noon struck as we were sitting down to table, when little Paul, delayed by his absorption in the expected event, suddenly ran to rejoin us, his cheeks glowing. Between his fingers we saw the fluttering wings of a handsome butterfly, caught but a moment before, while it was hovering in front of my study. He showed it me, questioning me with his eyes.

"Aha!" I cried, "this is precisely the pilgrim we are waiting for. Fold your napkin and come and see what happens. We will dine later."

Dinner was forgotten before the marvels that came to pass. With inconceivable punctuality the butterflies hastened to meet the magical call of the captive. With tortuous flight they arrived one by one. All came from the north. This detail is significant. A week earlier there had been a savage return of the winter. The bise blew tempestuously, killing the early almond blossom. It was one of those ferocious storms which in the South commonly serve as a prelude to the spring. But the temperature had now suddenly softened, although the wind still blew from the north.

Now on this first occasion all the butterflies hastening to the prisoner entered the garden from the north. They followed the direction of the wind; not one flew against it. If their guide was a sense of smell like ours, if they were guided by fragrant atoms suspended in the air, they should have arrived in the opposite direction. Coming from the south, we might believe them to be warned by effluvia carried on the wind; coming from the north in time of mistral, that resistless sweeper of earth and air, how can we suppose that they had perceived, at a remote distance, what we will call an odour? The idea of a flow of odoriferous atoms in a direction contrary to that of the aerial torrent seems to me inadmissible.

For two hours, under a radiant sun, the visitors came and went before the outer wall of the study. Most of them sought for a long time, exploring the wall, flying on a level with the ground. To see them thus hesitating you would say that they were puzzled to find the exact position of the lure which called them. Although they had come from such a distance without a mistake, they seemed imperfectly informed once they were on the spot. Nevertheless, sooner or later they entered the room and saluted the captive, without showing any great ardour. At two o'clock all was over. Ten butterflies had arrived.

During the whole week, and always about noon, at the hour of the brightest sunlight, the butterflies arrived, but in decreasing numbers. The total approached forty. I thought it useless to repeat experiments which would add nothing to what I had already learned. I will confine myself to stating two facts. In the first place, the Lesser Peacock is diurnal; that is to say, it celebrates its mating under the dazzling brilliance of noon. It needs the full force of the sunlight. The Great Peacock, on the contrary, which it so closely resembles both in its adult form and the work of its caterpillar, requires the darkness of the first hours of the night. Who can explain this strange contrast in habits?

In the second place, a powerful current of air, sweeping away in a contrary direction all particles that might inform the sense of smell, does not prevent the butterflies from arriving from a direction opposite to that taken by the effluvial stream, as we understand such matters.