Our Bruchus is not a sedentary inhabitant of the granaries: she needs the open air, the sunshine, the freedom of the fields. Very frugal on her own behalf, she absolutely disdains the hardness of the legumen; all that her slender snout requires is a few honeyed mouthfuls sipped from the flowers. The larva, on the other hand, demands the soft bread of the green pea still growing inside the pod. For these reasons, the storehouse knows no further multiplication on the part of the ravager introduced at the beginning.
The origin of the mischief lies out of doors. It is here more than elsewhere that we ought to keep a watch on the Weevil’s misdeeds, were it not that we are nearly always unarmed when it comes to fighting against insects. Indestructible because of their numbers, their small size, their sly cunning, the little creatures laugh at man’s anger. The gardener fumes and curses; the Weevil remains unconcerned: imperturbably she continues to levy her tithe.
Fortunately, we have assistants, more patient and more clear-sighted than ourselves. In the first week of August, when the adult Bruchus is beginning to move away, I make the acquaintance of a little Chalcis, the protector of our peas. In [[211]]my rearing-jars a number of her comes out of the Weevil’s home before my eyes. The female has a red head and thorax and a black abdomen, with a long boring-tool. The male, a little smaller, is clad in black. Both sexes have dull-red legs and thread-like antennæ.
In order to leave the pea, the exterminator of the Bruchus opens herself a window in the centre of the disk which the Weevil’s grub has bored in the skin with a view to its future deliverance. The devoured has prepared the way out for the devourer. This detail enables us to guess the rest.
When the preliminaries of the metamorphosis are finished, when the exit-hole is bored, furnished with its lid, a surface cuticle, the Chalcis comes bustling along. She inspects the peas, still on the plant, in their pods; she tries them with her antennæ; she discovers, hidden under the general outer wrapper of the pod, the weak points in the ceiling formed by the skin. Then, raising her sounding-rod, she thrusts it through the pod and pierces the thin lid. However deeply secreted in the centre of the pea, the Weevil, whether larva or nymph, is reached by the long implement. It receives an egg in its tender flesh; and the trick is done. Without any chance of defence, for it is by now either a torpid grub or else a nymph, the corpulent infant will be drained to the skin.
What a pity that we are not able at will to [[212]]promote the multiplication of this zealous exterminator! Alas, our agricultural auxiliaries have us in a disappointing vicious circle: if we wish to obtain the assistance of large numbers of the Chalcids that bore holes in peas, we must first have large numbers of Pea-weevils! [[213]]
Chapter xiii
THE HARICOT-WEEVIL
If there is a Heaven-sent vegetable on earth, it is the haricot bean. It has every good quality in its favour: it is soft to the tooth, of an agreeable flavour, plentiful, cheap and very nutritious. It is a vegetable flesh which, without being repulsive or dripping with blood, is as good as the cut-up horrors in the butcher’s shop. To emphasize its services to mankind, the Provençal idiom calls it gounflo-gus, the poor man’s bellows.[1]