The larva’s methods remind us at all points of what the Pea-weevil showed us. Each grub digs itself a cell in the floury mass, while respecting the skin in the form of a protective disk, which the adult will easily be able to push out at the moment of leaving. Towards the end of the larval phase, the cells show through on the surface of the bean as so many dark circles. At last the lid falls off, the insect leaves its cell and the haricot remains pierced with as many holes as it had grubs feeding on it. Very frugal, satisfied with a few floury scraps, the adults seem not at all anxious to abandon the heap so long as beans worth exploiting remain. They mate in the interstices of the stack; the mothers scatter their eggs at random; the young grubs make themselves at home, some in the untouched haricots, some in the beans that are holed but not yet exhausted; and the swarming is repeated every five weeks throughout the summer, after which the last generation, the one born in September or October, slumbers in its cells till the return of the warm weather. If ever the spoiler of the haricots became too ominously threatening, it would not be very difficult to wage a war of extermination upon her. We know from her habits the best tactics to follow. She ravages the dry and gathered crop, stored in the granaries. It is an irksome matter to attend to her in the open fields; and it is also almost useless. The bulk of her business is conducted elsewhere, in our warehouses. The enemy settles down under our roof, within our reach. This being so, with the aid of insecticides defence becomes relatively easy. CHAPTER XIV THE IRIS-WEEVIL Plants, with their fruits, have been and still are the main sustenance of mankind. The ancient Paradise of which the eastern legends tell us had no other food-resources. It was a delicious garden with cool rivulets and fruits of every kind, including the apple that was to be so fatal to us. On the other hand, from a very early period, our ills sought to obtain relief by the virtues of simples, virtues that were sometimes real and sometimes, indeed most frequently, imaginary. Our knowledge of plants is thus as old as our infirmities and our need of food. Our knowledge of insects, on the contrary, is quite recent. The ancients knew nothing of the lesser animals, did not even deign to glance at them. This disdain is by no means extinct. We are vaguely familiar with the work of the Bee and the Silk-worm; we have heard people speak of the industry of the Ant; we know that the Cicada sings, without having a very exact notion of the singer, who is confused with others; we have perhaps vouchsafed a careless glance to the splendours of the Butterflies; and with this, for the immense majority, entomology begins and ends. What layman would risk naming an insect, even one of the more remarkable?