A second point is open to discussion. The three nests found under the stones are in a piteous state. Soaked with damp, they possess hardly more consistency than the muddy puddle utilized for their construction. They are softened to such a degree that they can no longer be handled. The cells are ripped open; the cocoons, easily recognizable by their colour and their transparency, which is that of an onion-skin, are in pieces, without any vestige of the larvæ which I ought to find at the time of my discovery, that is in winter. And yet the three hovels are not old nests ruined by the weather after the emergence of the perfect insect, for the exit-doors are still closed with their well-fitting plugs. It is at an abnormal place, in the side, that the yawning breach occurs. The escaping insect would never use such violence in breaking through. They are certainly recent nests, nests of the previous summer. Their dilapidation is due to their unprotected position. The rain penetrates into the stone-heaps; even under the shelter of a flagstone the air is saturated with damp. If a little snow falls, the mischief is still worse. In this way, the wretched nests crumble and fall to pieces, leaving the cocoons partly exposed. Unprotected by their earthen sheath, the larvæ have become the prey of the brigandage that mows down the weak. Some Field-mouse passing by has perhaps feasted on those tender morsels. At the sight of these ruins a suspicion occurs to me. Is the primitive art of the Pelopæus really practicable in my region? When nesting in stone-heaps, does the tiny potter find the security needed for her family, especially during the winter? It is very doubtful. The extreme rarity of the nests in such conditions is evidence of the mother’s aversion for these sites; and the dilapidated state of those which I find seems to testify to their dangerous nature. If the inclemency of the climate makes it impossible for the Pelopæus to practise the industry of her forebears successfully, does not this prove that the insect is a stranger, a colonist from a hotter and drier climate, where there is no persistent rain and above all no snow to be dreaded?