Note 9 — CHAP. II. OF THE EGGS, LARVÆ, AND PUPÆ OF ANTS.

M. Latreille has remarked, as well as De Geer, that, among the Ash-coloured Ants, there are some pupæ which are naked, others enclosed in a cocoon; but he does not know if there are any that undergo their metamorphosis without spinning, or if the workers tear off their enveloping membrane; however he leans to this latter opinion. I have often made the same remark. I have even confirmed the conjecture he had advanced, and often seen the ash-coloured labourers opening the cocoon of the pupæ, a short period after their transformation. The Mining Ants act the same: but for what purpose do they hasten to liberate them, and of what advantage is it to the larvæ to spin, if the workers so soon destroy the tissue they have woven? It cannot be for the sake of unfolding their members from the last envelope in the state of pupæ, for the ants do not render them this service until they are capable of motion, and have acquired their full strength: they even know the precise moment when to remove them. Are not these cocoons of essential service to the larvæ at the time of passing to the state of pupæ? I have frequently drawn from their cocoons, larvæ which had just spun, and which were not yet metamorphosed: some days after, they began rejecting their larva-skin, but could not disengage their limbs, which, with the abdomen, remained attached to it. The ants offered them no assistance. These pupæ were never well developed, and they soon perished. It appears that these cocoons offered them a point of support, enabling them to free themselves from the skin which they are under the necessity of rejecting. It will be objected, perhaps, that the larvæ of several species never spin, and they would of course experience the same inconvenience as those I drew too hastily from their cocoon. To this I answer, that nature has provided for this case in another manner:—the body of these Ants is very different from that of others, their elongated peduncle gives greater liberty to the abdomen, to move, bend, and extend itself, than the peduncle of the first, which is closely attached to the corslet. They have, in addition, a sting, which may also facilitate their developement, for the pupæ at first possess much strength and vivacity, although they soon after pass into a state of lethargy.—A.