146 Bird - Lore it seems, he can only move himself on the axis of the same route, and there is for him only two solutions, the right and the wrong. In coming back to France we sent out some American Pigeons, which all took their bearings without hesitation over the wake of the vessel and took up the reverse scent of the route followed. On nearing Europe we sent out at 900, 600, and 400 kilometers some French Pigeons which had been shut up on board the vessel and kept to be released on the return trip. We noticed that all having the same idea of following the route took their initial direc- tion over the wake of the vessel, flying toward New York. The greater number changed their minds and came back, afterward out- stripping the steamer in its homeward voyage. But the losses were greater than in going, reaching the proportion of 20 per cent. These are evidently the Pigeons which, skirting closely the reverse scent of the route followed, went astray in the open sea. We assert once more that the land does not appear to exercise any attraction for our messengers. Sent out from the Scilly Islands, from the island d'Aurigny, or the peninsulas of Cotentin, they all follow the same direction — east, west — some going in advance of the vessel, others following the reverse scent of its route. The Pigeons rise a little higher than at the time of leaving France ; the weather is clearer, but they do not seem to have recourse to the sense of seeing in order to take their bearings. None of them bent his flight over the land in sight. We have verified by a late experience, very easy to reproduce, that observation through the medium of the five senses amounts to noth- ing in guiding them back to the Pigeon cote. Five Pigeons under the influence of chloroform are transported from Orleans to Evreux. They do not know this last locality, where we are taking them for the first time. They are watched with great care and when, two days after, they appear to have returned to their normal condition, we set them at liberty and they return as usual. It seems that the chloroform suppresses the exercise of the five senses, which have during the journey registered no impression, and are mute at the awakening. The sense of direction, on the contrary, whose action is based on the automatic and mechanical registration of the road followed, cou- tinued to work, in spite of the chloroform, absolutely like other me- chanical functions — the circulation of the blood, the digestive organs, and respiration- — in some way, without the knowledge of the animal. We have vainly sought for a theory in the works of naturalists which explains in any satisfactory way the acts of orientation accom-
