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482 secret, so in the capricious flight of a bird or the wandering course of a wild animal chance has, as we believe, no part.

The motive which determines the actions of the animal is the instinct of preservation of the individual and of the species. The animal is capable of a spontaneous activity when he is roused by necessity; it is very seldom that he performs an act that has no immediately useful end. Initiative is not within his power, and when, in ants or bees, we think we have observed forethought for the future, we soon see that this supposed provision is nothing more than obedience to the momentary call of instinct: the animal accomplishes an action without foreseeing the result.

The search for food and sleep are the two poles between which the existence of an animal constantly gravitates. If, to utilize the resources of his domain, he is obliged to vary his course daily, the periodic need for rest yet brings him back to the same quarters. The lack of initiative leads him to always follow the same road to return to the same point. This is why the animal on his domain makes a number of trails which are interwoven in every direction; he acquires in this way a very complete knowledge of the locality; in the region where every little irregularity is familiar to him he is ready to move in every direction.

Necessity may force the inhabitant of one region to overstep its limits, in time of drought or famine, for example. Then he makes a rapid incursion into the neighboring territory, delays not a moment, but as soon as he has quenched his thirst or appeased his hunger returns in all haste to his home. In this second region, seldom fully explored, the animal knows but a limited number of trails, usually straight ones. If he is surprised there by a danger of any kind, he is much more exposed than in his own territory.

One example will show plainly the essential difference existing between these two zones. When a stag is attacked in his own domain by hunters, he begins by doubling, makes a thousand turns, and for a time throws his adversaries off the track. Soon again discovered, he sets out anew; pursued from shelter to shelter he finally "gets away" and plunges into the second zone, where the trails are straight. The chase then changes its character, and takes on a rapid pace which it did not have in its first phase.

The stag soon reaches the limits of the known territory and tries to return on his tracks and regain his own domain. Constantly driven back, pressed closely by the dogs, he again sets out, crosses the second zone, and then, entering the unknown territory, he is "off," running straight forward until he falls.

It is interesting to see how a stag acts who has been carried some distance in a cage and then set at liberty before a hunting party to be chased. The animal, cast on an unknown ground, does not try to