Fig. 66, taken from the Memoir published by M. Guérin-Méneville, in the "Revue Nouvelle" of the 15th July, 1847, shows the Dacus laying its eggs on the olive, and the larvæ that are already hatched in another of the same fruit. The larvæ which succeed these eggs (Fig. 67) are whitish, soft, and without limbs. They pass fifteen or sixteen days in boring a gallery in the pulp of the olive, at first vertically, until they reach the stone, then on one side, and along the side of the stone. When they have reached the term of their development, they approach the surface, enlarging the first channel and leaving between it and the exterior air only a thin pellicle, in the middle of which may be perceived the first small opening by which the mother had introduced her egg in the commencement. [Illustration: Fig. 67.--Larvæ of Dacus oleæ (magnified and natural size).] [Illustration: Fig. 68.--Gallery formed by larva of Dacus oleæ.] Fig. 68, copied from a drawing in the Memoirs of M. Guérin-Méneville, shows the gallery bored round the olive by the larva of the Dacus. The larva thus prepares an easy issue for the perfect insect. Its skin then contracts, its body diminishes in length, and is transformed into an oval cocoon, which soon gets brown, and is the chrysalis of the insect. At the side of the head it shows a curved line, a thin suture which marks a sort of cap or door, which, at the time of its hatching, the insect will be easily able to force open with its head. The fly is hatched twelve days after its metamorphosis from the larva to the pupa. It has thus taken the Dacus twenty-seven to twenty-eight days to arrive at this state, from the time the egg was laid; besides which, this species, in the warm climates of Provence and Italy, can reproduce itself several times from the beginning of July, the period at which the first flies begin to lay, till the end of autumn.