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must assuredly be always present—when an instinct comes into operation. It continues to hold good, therefore, that the power of foreseeing the weather is a case of unconscious clairvoyance, of which the stork which takes its departure for the south four weeks earlier than usual knows no more than does the stag when before a cold winter he grows himself a thicker pelt than is his wont.
On the one hand, animals have present in their consciousness a perception of the actual state of the weather; on the other, their ensuing action is precisely such as it would be if the idea present with them was that of the weather that is about to come. This they cannot consciously have; the only natural intermediate link, therefore, between their conscious knowledge and their action is supplied by unconscious idea, which, however, is always accurately prescient, inasmuch as it contains something which is neither given directly to the animal through sensual perception, nor can be deduced inferentially through the understanding.
Most wonderful of all are the instincts connected with the continuation of the species. The males always find out the females of their own kind, but certainly not solely through their resemblance to themselves. With many animals, as, for example, parasitic crabs, the sexes so little resemble one another that the male would be more likely to seek a mate from the females of a thousand other species than from his own. Certain butterflies are polymorphic, and not only do the males and females of the same species differ, but the females present two distinct forms, one of which as a general rule mimics the outward appearance of a distant but highly valued species; yet the males will pair only with the females of their own kind, and not with the strangers, though these may be very likely much more like the males themselves. Among the insect species of the strepsiptera, the female is a shapeless worm which lives its whole life long in the hind body of a wasp; its head, which is of the shape of a lentil, protrudes between two of the belly rings of the wasp, the rest of its body being inside. The male, which only lives for a few hours, and resembles a moth, nevertheless recognises his mate in spite of these adverse circumstances, and fecundates her.
Before any experience of parturition, the knowledge that it is approaching drives all mammals into solitude, and bids them prepare a nest for their young in a hole or in some other place of shelter. The bird builds her nest as soon as she feels the eggs coming to maturity within her. Snails, land-crabs, treefrogs, and toads, all of them ordinarily dwellers upon land, now betake themselves to the water; sea-tortoises go on shore, and many salt-water fishes come up into the rivers in order to lay their eggs where they can alone find the requisites for their development. Insects lay their eggs in the most varied kinds of situations,— in sand, on leaves, under the hides and horny substances of other animals; they often select the spot where the larva will be able most readily to find its future sustenance, as in autumn upon the trees that will open first in the coming spring, or in spring upon the blossoms that will first bear fruit in autumn, or in the insides of those caterpillars which will soonest as chrysalises provide the parasitic larva at once with food and with protection. Other insects select the sites from which they will first get forwarded to the destination best adapted for their development. Thus some horseflies lay their eggs upon the lips of horses or upon parts where they are accustomed to lick themselves. The eggs get conveyed hence into the entrails, the proper place for their development,—and are excreted upon their arrival at maturity. The flies that infest cattle know so well how to select the most vigorous and healthiest beasts, that cattle-dealers and tanners place entire dependence upon them, and prefer those beasts and hides that are most scarred by maggots. This selection of the best cattle by the help of these flies is no evidence in support of the conclusion that the flies possess the power of making experiments consciously and of reflecting thereupon, even though the men whose trade it is to do this recognise them as their masters. The solitary wasp makes a hole several inches deep in the sand, lays her egg, and packs along with it a number of green maggots that have no legs, and which, being on the point of becoming chrysalises, are well nourished and able to go a long time without food; she packs these maggots so closely together that they cannot move nor turn into chrysalises, and just enough of them to support the larva until it becomes a chrysalis. A kind of bug (cerceris bupresticida), which itself lives only upon pollen, lays her eggs in an underground cell, and with each one of them she deposits three beetles, which she has lain in wait for and captured when they were still weak through having only just left off being chrysalises. She kills these beetles, and appears to smear them with a fluid whereby she preserves them fresh and suitable for food. Many kinds of wasps open the cells in which their larvae are confined when these must have consumed the provision that was left with them. They supply them with more food, and again close the cell. Ants, again, hit always upon exactly the right moment for opening the cocoons in which their larvse are confined and for setting them free, the larva being unable to do this for itself. Yet the life of only a few kinds of insects lasts longer than a single breeding season. What then can they know about the contents of their eggs and the fittest place for their development? What can they know about the kind of food the larva will want when it leaves the egg—a food so different from their own? What, again, can they know about the quantity of food that will be necessary? How much of all this at least can they know consciously? Yet their actions, the pains they take, and the importance they evidently attach to these matters, prove that they have a foreknowledge of the future: this knowledge therefore can only be an unconscious clairvoyance. For clairvoyance it must certainly be that inspires the will of an animal to open cells and cocoons at the very moment that the larva is either ready for more food or