moment when the egg is laid the _Sitaris_ larva springs upon it. Even while the poor mother is carefully fastening up her cell, her mortal enemy is beginning to devour her offspring: for the egg of the Anthophora serves not only as a raft, but as a repast. The honey which is enough for either, would be too little for both; and the _Sitaris_, therefore, at its first meal, relieves itself from its only rival. After eight days the egg is consumed, and on the empty shell the _Sitaris_ undergoes its first transformation, and makes its appearance in a very different form, as shown in Fig. 10. The honey which was fatal before is now necessary; the activity which before was necessary is now useless; consequently, with the change of skin, the active, slim larva changes into a white, fleshy grub, so organized as to float on the surface of the honey, with the mouth beneath, and the spiracles above the surface: “grâce à l’embonpoint du ventre,” says M. Fabre, “la larve est à l’abri de l’asphyxie.” In this state it remains until the honey is consumed; then the animal contracts, and detaches itself from its skin, within which the further transformations take place. In the next stage, which M. Fabre calls the pseudo-chrysalis (Fig. 11), the larva has a solid corneous envelope and an oval shape; and in its colour, consistency, and immobility reminds one of a Dipterous pupa. The time passed in this condition varies much. When it has elapsed, the animal moults again, again changes its form, and assumes that shown in Fig. 12; after this it becomes a pupa (Fig. 13) without any remarkable peculiarities. Finally, after these wonderful changes and adventures, in the month of August the perfect _Sitaris_ (Pl. III., Fig. 4) makes its appearance. On the other hand, there are cases in which larvæ diverge remarkably from the ordinary type of the group to which they belong, without, as it seems in our present imperfect state of information, any sufficient reason.