Let us take our scissors and rip open the nest from end to end longitudinally. A wide window opens and allows us to see the arrangement of the inside. The first thing to strike us is that the leaves contained in the enclosure are intact and quite sound. The young caterpillars in their temporary establishments gnaw the leaves within the silken wrapper to death; they thus have their larder stocked for a few days without having to quit their shelter in bad weather, a condition made necessary by their weakness. When they grow stronger and start working on their winter home, they are very careful not to touch the leaves. Why these new scruples? The reason is evident. If bruised, those leaves, the framework of the house, would very soon wither and then be blown off with the first breath of wind. The silken purse, torn from its base, would collapse. On the other hand, if the leaves are respected, they remain vigorous and furnish a stout support against the assaults of winter. A solid fastening is superfluous for the summer tent, which lasts but a day; it is indispensable to the permanent shelter which will have to bear the burden of heavy snows and the buffeting of icy winds. Fully alive to these perils, the spinner of the pine-tree considers himself bound, however importunate his hunger, not to saw through the rafters of his house. Inside the nest, therefore, opened by my scissors I see a thick arcade of green leaves, more or less closely wrapped in a silky sheath whence dangle shreds of cast skin and strings of dried droppings. In short, this interior is an extremely unpleasant place, a rag-shop and a sewage-farm in one, and corresponds in no way with the imposing exterior. All around is a solid wall of quilting and of closely-woven leaves. There are no chambers, no compartments marked off by partition-walls. It is a single room, turned into a labyrinth by the colonnade of green leaves placed in rows one above the other throughout the oval hall. Here the caterpillars stay when resting, gathered on the columns, heaped in confused masses. When we remove the hopeless tangle at the top, we see the light filtering in at certain points of the roof. These luminous points correspond with the openings that communicate with the outer air. The network that forms a wrapper to the nest has no special exits. To pass through it in either direction, the caterpillars have only to push the sparse threads aside slightly. The inner wall, a compact rampart, has its doors; the flimsy outer veil has none.