have made cm this subject a very curious observation. When a basket of pigeons which have already performed journeys is carried by rail-road, they manifest great agitation when they reach a station whence they have formerly been released, although they remained indifferent whenever they stopped at previous stations. Now, it will certainly be admitted that a pigeon inclosed in a basket, which in turn is shut up in a dark carriage, can not, from the noise alone, distinguish one station from another. Its sight and its other senses are of no use to it, since it is as completely as possible isolated from whatever passes outside, and yet it knows exactly where it is in respect to the point of its departure. We were right, then, in saying that an animal carried to a a distance possesses an entirely subjective idea of his situation independent of the surroundings through which he is for the moment passing.
Mythology relates how Theseus, penetrating the mazes of the labyrinth, held in his hand the thread given him by Ariadne. He could in this way go back on his own track and reach the entrance to the chasm. Does it not seem that the animal possesses likewise the thread of Ariadne, and unrolls it whenever he enters unknown regions?
Before we pass to a new course of thought, let us stop for an instant to consider an objection which naturally occurs to us. We have cited in support of our last deduction some observations made on the carrier pigeon. Since the organ of distant orientation has been developed by a wise selection in this interesting messenger, can we generalize and apply to other animals the remarks which concern it? We do not hesitate to answer such a question affirmatively. By selection man develops a certain faculty abnormally to the detriment of some other; he deforms the primitive type, often destroys the equilibrium of nature for his own profit. He can not, however, develop a new faculty; he must limit himself to only modifying the existing ones. Variation and heredity are, in fact, the only means which he can use to accomplish his purpose. We can not, therefore, discover in the carrier pigeon any trait which did not exist in the germ in its wild ancestor.
If a new example seems, nevertheless, necessary to confirm this theory, we will cite another interesting fact from the history of migratory birds. In 1883, on a dark night during a heavy squall, a flock of wild geese alighted at Clermont-Ferrand on the church of St. Eutrope and the neighboring houses. After a stay of two hours, the wind having lulled, the birds took up their interrupted journey through the air. Some of them, however, who had descended into the gardens or into the courts, did not succeed in taking flight. They struck against the walls or got entangled in the trees. Some were killed and others so badly wounded that they were picked up the next morning by the people.
The wild goose has not an eye formed like that of nocturnal birds. Deprived of sight by exceptional darkness, these birds did not, how-
