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Show 1881.] MISS A. CRANE ON THE MANATEE. 457 the area of these quarters appears somewhat limited when compared with the bulk of the animals, the Manatees seem perfectly comfortable and, being of a sluggish disposition, rarely explore the whole of their small domain. Nor do they, so far as I have observed, avail themselves of the shallowness of the water and, by supporting their bodies on the tail-fin, keep their heads above the surface and avoid the constant repetition of the upward movement in order to breathe the necessary air. They habitually rest side by side at the bottom of the tank, with the caudal fin stretched out quite straight, and the tips of the fore fins just touching the ground (see sketch). Sketch of the Manatee in the Brighton Aquarium. Thence they rise gently, often with the least perceptible movement of the tail and flapping motion of the paddles, raising the upper part of the body until the head reaches the surface, when the air is admitted through the nostril flap valves, which are closely shut after the operation, and the original and usual position is gently resumed. They seem generally to be compelled to rise to the surface for aerial respiration every two or three minutes ; but the interval between respiration varies much at different times. In one quarter of an hour, during which one was carefully timed, it rose nine times, at very irregular intervals. I have been informed that they occasionally remain under water for a much longer period; but have never observed them to exceed six minutes, although I have timed them before and after feeding, and at all hours of the day. The respiratory movement appears to be repeated almost mechanically and without effort. When the water is run off in the early morning, the animals are left stranded on the floor; and the strength latent in the caudal fin becomes apparent, as it is struck violently on the dry floor of their tank when they are approached or disturbed. But the Manatees rarely make any serious attempt at progression, merely rolling lazily over from side to side. Indeed the small fore paddles seem ludicrously inadequate for the support of the unwieldy body in the act of terrestrial locomotion, although the animals move with easy grace in their native element. The fore fins are then often employed, when swimming slowly, the tips being applied to the PROC. ZOOL. Soc-1881, No. XXX. 30 |