Disappointment awaited me.  May arrived; a capricious month which set my preparations at naught, troublesome as these had been.  Winter returned.  The mistral shrieked, tore the budding leaves of the plane-trees, and scattered them over the ground.  It was cold as December.  We had to light fires in the evening, and resume the heavy clothes we had begun to leave off.

My butterflies were too sorely tried.  They emerged late and were torpid.  Around my cages, in which the females waited—­to-day one, to-morrow another, according to the order of their birth—­few males or none came from without.  Yet there were some in the neighbourhood, for those with large antennae which issued from my collection of cocoons were placed in the garden directly they had emerged, and were recognised.  Whether neighbours or strangers, very few came, and those without enthusiasm.  For a moment they entered, then disappeared and did not reappear.  The lovers were as cold as the season.

Perhaps, too, the low temperature was unfavourable to the informing effluvia, which might well be increased by heat and lessened by cold as is the case with many odours.  My year was lost.  Research is disappointing work when the experimenter is the slave of the return and the caprices of a brief season of the year.

For the third time I began again.  I reared caterpillars; I scoured the country in search of cocoons.  When May returned I was tolerably provided.  The season was fine, responding to my hopes.  I foresaw the affluence of butterflies which had so impressed me at the outset, when the famous invasion occurred which was the origin of my experiments.

Every night, by squadrons of twelve, twenty, or more, the visitors appeared.  The female, a strapping, big-bellied matron, clung to the woven wire of the cover.  There was no movement on her part; not even a flutter of the wings.  One would have thought her indifferent to all that occurred.  No odour was emitted that was perceptible to the most sensitive nostrils of the household; no sound that the keenest ears of the household could perceive.  Motionless, recollected, she waited.

The males, by twos, by threes and more, fluttered upon the dome of the cover, scouring over it quickly in all directions, beating it continually with the ends of their wings.  There were no conflicts between rivals.  Each did his best to penetrate the enclosure, without betraying any sign of jealousy of the others.  Tiring of their fruitless attempts, they would fly away and join the dance of the gyrating crowd.  Some, in despair, would escape by the open window:  new-comers would replace them:  and until ten o’clock or thereabouts the wire dome of the cover would be the scene of continual attempts at approach, incessantly commencing, quickly wearying, quickly resumed.

Every night the position of the cage was changed.  I placed it north of the house and south; on the ground-floor and the first floor; in the right wing of the house, or fifty yards away in the left wing; in the open air, or hidden in some distant room.  All these sudden removals, devised to put the seekers off the scent, troubled them not at all.  My time and my pains were wasted, so far as deceiving them was concerned.