The comparison with a draw-plate comes in quite aptly here: the larva actually frees itself by a wire-drawing-operation. Like a length of brass wire which is reduced by being passed through an orifice too narrow for its diameter, it escapes through the window in the shell by decreasing its girth. The wire is drawn by an exertion on the part of the workman’s pincers or by the rotation of the machine; it subsequently retains the reduced thickness which the operation has given it. The grub knows another method: it lengthens and thins itself by its own efforts; and, directly it has passed through the narrow orifice, it returns to its natural size. Apart from these differences the resemblance is striking. The exit-aperture is precisely the same width as the head, which, being rigid, with a horny cap, does not lend itself to deformation. Where the head has passed, the body has to pass, however fat it may be. When the liberation is completed, it is most surprising to see how bulky a cylinder, how corpulent a grub has contrived to make its way through the tiny opening. If we had not witnessed the exodus, we should never have suspected such a feat of gymnastics. The orifice, we were saying, is exactly fitted to the diameter of the head. Now this inelastic head, by whose size that of the hole has been calculated, represents at most one-third of the width of the body. How does a threefold thickness pass through a single calibre? Here comes the head, without the least difficulty: it is the pattern to which the door was built. The neck, a little wider, follows: a slight contraction frees it. Next comes the turn of the chest and the plump belly. This is a most arduous operation. The grub has no legs. It has nothing, neither hooks nor stiff bristles, that might give it a purchase. It is a soft roly-poly which has, by its own efforts, to clear the disproportionately narrow passage. What happens inside the nut escapes me: it is hidden by the opaque shell; what I see outside is very simple and tells me of that which cannot be seen. The creature’s blood rushes from back to front; the humours of the organism change their position and accumulate in the part that has already emerged, which swells into a dropsy, attaining five or six times the diameter of the head. In this way a large cushion is formed on the kerb of the well, a girdle of energy which, by its dilatation and its intrinsic elasticity, gradually extricates the remaining segments, which are diminished in volume by the shifting of their fluid contents. It is a slow and very laborious business. The grub, in its free part, bends, draws itself up and sways from side to side. We do the same when forcing a nail from side to side to extract it from its socket. The mandibles gape widely, close and gape again, with no intention of laying hold. These movements represent the yo-heave-hoes with which the exhausted creature accompanies its efforts, like those of sailors hauling on a cable.