The little bug, whose forehead is too soft, covers her head, to raise the lid of the box, with a mitre formed of three triangular rods, which is always at the bottom of the egg at the moment of delivery. Her limbs being sheathed like those of a mummy, she has nothing wherewith to put her rods in motion except the pulsations produced by the rhythmic flow of blood in her skull and acting after the manner of a piston. The rivets of the lid gradually give way; and, as soon as the insect is free, it lays aside its mechanical helmet. Another species of bug, _Reduvius personatus_, who lives mostly in lumber-rooms, where she lies hidden in the dust, has invented a still more astonishing system of hatching. Here, the lid of the egg is not riveted, as in the case of the Pentatomae, but simply glued. At the moment of liberation, the lid rises and we see: “... a spherical vesicle emerge from the shell and gradually expand, like a soap-bubble blown through a straw. Driven farther and farther back by the extension of this bladder, the lid falls. “Then the bomb bursts; in other words, the blister, swollen beyond its capacity of resistance, rips at the top. This envelope, which is an extremely tenuous membrane, generally remains clinging to the edge of the orifice, where it forms a high, white rim. At other times, the explosion loosens it and flings it outside the shell. In those conditions, it is a dainty cup, half spherical, with torn edges, lengthened out below into a delicate, winding stalk.” Now, how is this miraculous explosion produced? Fabre assumes that: “Very slowly, as the tiny creature takes shape and grows, this bladder-shaped reservoir receives the products of the work of respiration performed under the cover of the outer membrane. Instead of being expelled through the egg-shell, the carbonic acid, the incessant result of the vital oxidization, is accumulated in this sort of gasometer, inflates and distends it and presses upon the lid. When the insect is ripe for hatching, a superadded activity in the respiration completes the inflation, which perhaps has been preparing since the first evolution of the germ. At last, yielding to the increasing pressure of the gaseous bladder, the lid becomes unsealed. The chick in its shell has its air-chamber; the young Reduvius has its bomb of carbonic acid: it frees itself in the act of breathing.” 9