Does not the Mason-bee, "which rakes the roads for a dry powdery dust and mixes it with saliva to convert it into a hard cement," foresee that this mud will harden? Is the Pelopaeus devoid of judgment when she seeks the interior of dwelling-houses in order to shelter her nest of dried clay, which the least drop of rain would reduce to its original state of mud? Is it without knowledge of the effects that the sloe-weevil builds a ventilating chimney to prevent the asphyxiation of her larva? that the Scarabaeus sacer contrives a filter at the smaller end of its pear-shaped ball, by means of which the grub is able to breathe? or that Arachne labyrintha "introduces in her silk-work a rampart of compressed earth to protect her eggs from the probe of the Ichneumon"? May we not also see a masterpiece of the highest logic in the house of the trap-door spider, Arachne clotho, which is furnished with a door, a true door "which she throws open with a push of the leg, and carefully bolts behind her on returning by means of a little silk"? (8/13.) What a miracle of invention too is the prodigious nest of the Eumenes, "with its egg suspended by a thread from the roof, like a pendulum, oscillating at the lightest breath in order to save it from contact with the caterpillars, which, incompletely paralysed, are wriggling and writhing below"! Later, when the egg is hatched, "the filament is transformed into a tube, a place of refuge, up which the grub clambers backwards. At the least sign of danger from the mass of caterpillars the larva retreats into its sheath and ascends to the roof, where the wriggling swarm cannot reach it." (8/14.) Let us refer also to the remarkable history of the Copris. We cannot deny that the valiant dung-beetle is capable of "evading the accidental" (which to Fabre constitutes one of the distinctive characteristics of the intelligence), since it immediately intervenes if with the point of a penknife we open the roof of its nest and lay bare its egg. "The fragments raised by the knife are immediately brought together and soldered, so that no trace is left of the injury, and all is once more in order." We may read also with what incredible address the mother Copris was able to use and to profit by the ready-made pellets of cow-dung which it occurred to Fabre to offer her. (8/15.) But their scope is limited, and encroaches very little, in the eyes of the great observer, on the domain of intelligence. This he demonstrates to satiety, and his astonishing Necrophori, which adapt themselves so admirably to circumstances and triumph over the experimental difficulties to which he subjects them, seem scarcely to exceed the limits of those actions which at bottom are merely unconscious. (8/16.) With the spawning of the Osmia, Fabre throws a fresh and unexpected light on the intuitive knowledge of instinct.