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Show 316 MR. G. E. DOBSON ON T H E [May I 9, down, and again renewed the same attempt more vigorously. Five minutes afterwards it rose again, and pushed strongly against the net. Thirty minutes afterwards it swam about excitedly round and round the vessel. Two hours subsequently, in some way I did not perceive, it splashed water up through the double net violently, so that some drops fell outside the jar, the mouth of which was nearly 4 inches above the surface of the water. Fifteen minutes afterwards I saw the fish resting vertically on the extremity of the caudal fin, having its head thrust through one of the meshes of the lower net, and the extremity of the snout at the surface of the water through a mesh of the upper net. The depth of the water was such that the fish exactly reached the surface with the snout when suspended vertically resting on the tip of the caudal fin. The netted diaphragm was now raised 1 inch higher, and water added, so that the net was 1 inch beneath the surface. In thirty-seven minutes the fish again sought the surface, and succeeded in thrusting its head and part of its body through the meshes of both nets, so that its muzzle rested at the surface of the water. In this position it remained quiet, apparently drawing in the unmixed air, and would only leave its position when touched several times. Soon afterwards it again forced its way through the net as before ; and two minutes afterwards some bubbles of air passed from its mouth. On shaking the vessel some air-bubbles passed upwards from the gill-openings. The net was now removed and a perforated tin plate substituted. In forty-five minutes the fish swam about in an excited manner, and then sank to the bottom. It made several attempts to reach the surface, and at length managed to force itself through a somewhat larger opening in the centre of the plate, which I had thought much too small for it to get through. Immediately on reaching the surface it discharged a large amount of air under water, as a great number of bubbles came up about it. It remained in shallow water (about half an inch deep) all next day, and appeared very lively in the evening. On the following day I observed that soon after taking in air at the surface and sinking to the bottom of the vessel, a large amount of air passed upwards in bubbles from the anus. The fish was removed to a larger jar, fresh water placed in it, and a tin plate pierced throughout with openings of an equal size, too small to allow the animal to gain access to the surface. The fish made many attempts unsuccessfully to reach the surface, and at length sank to the bottom and remained quiet there, the gill-covers moving, however, very rapidly. In twenty-four hours the fish was evidently about to die; the dorsal fin had collapsed, and the gill-covers had almost ceased to move. The diaphragm was removed, and fresh water placed in the jar. The fish immediately recovered strength, the dorsal fin became erect, and respiration proceeded as before. On the following night he again leaped out of the jar, and was found dead on the floor next morning. Exp. 6.-Another specimen of Lepidocephalicthys balgara was placed in the glass jar in about 3 inches of water without the |