I place on a plate two or three handfuls of the infested haricots, and set the populous heap in the full sunlight by the edge of my bed of beans.  I can imagine what will happen.  Those insects which are already free, and those which the stimulus of the sunshine will presently liberate, will emerge and take to their wings.  Finding the maternal haricot close at hand they will take possession of the vines.  I shall see them exploring pods and flowers, and before very long they will lay their eggs.  That is how the pea-weevil would behave under similar conditions.

But no:  to my surprise and confusion, matters do not fall out as I foresaw.  For a few minutes the insects bustle about in the sunlight, opening and closing their wing-covers to ease the mechanism of flight; then one by one they fly away, mounting in the luminous air; they grow smaller and smaller to the sight, and are quickly lost to view.  My persevering attentions have not met with the slightest success; not one of the weevils has settled on my haricots.

When the joys of liberty have been tasted will they return—­to-night, to-morrow, or later?  No, they do not return.  All that week, at favourable hours, I inspect the rows of beans pod by pod, flower by flower; but never a Bruchus do I see, nor even an egg.  Yet the season is propitious, for at this very moment the mothers imprisoned in my jars lay a profusion of eggs upon the dry haricots.

Next season I try again.  I have at my disposal two other beds, which I have sown with the late haricot, the red haricot; partly for the use of the household, but principally for the benefit of the weevil.  Arranged in convenient rows, the two crops will be ready, one in August and one in September or later.

With the red haricot I repeat the experiment already essayed with the black haricot.  On several occasions, in suitable weather, I release large numbers of weevils from my glass jars, the general headquarters of the tribe.  On each occasion the result is plainly negative.  All through the season, until both crops are exhausted, I repeat my search almost daily; but I can never discover a single pod infested, nor even a single weevil perching on leaf or flower.

Certainly the inspection has not been at fault.  The household is warned to respect certain rows of beans which I have reserved for myself.  It is also requested to keep a look-out for eggs on all the pods gathered.  I myself examine with a magnifying-glass all the haricots coming from my own or from neighbouring gardens before handing them over to the housewife to be shelled.  All my trouble is wasted:  there is not an egg to be seen.

To these experiments in the open air I add others performed under glass.  I place, in some tall, narrow bottles, fresh haricot pods hanging from their stems; some green, others mottled with crimson, and containing seeds not far from mature.  Each bottle is finally given a population of weevils.  This time I obtain some eggs, but I am no further advanced; they are laid on the sides of the bottles, but not on the pods.  Nevertheless, they hatch.  For a few days I see the grubs wandering about, exploring the pods and the glass with equal zeal.  Finally one and all perish without touching the food provided.