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Show 280 DR. F. DAY ON INDIAN FRESHWATER FISHES. [May 14, survive even longer, as when it had been seven hours out of water it was opened, and the heart was found still pulsating, although the body was as hard and stiff as a piece of board from the mucus which had exuded and dried over it. A specimen of the O. striatus, 18 inches long, was wrapped up alive in a dry cloth and locked in a close cupboard, where it lived for 16 hours. Experiment No. 10.-As these fishes had been proved to live tor some time altogether without water, and again in water when unable to pass it through their gills, it appeared probable that the inhalation of chloroform would affect them. Therefore, at 9.30 a.m. an Ophiocephalus striatus, of upwards of a foot in length, was placed m the glass globe of a hanging lamp, the top of which was covered over by a thick towel; ten drops of chloroform were then administered, and repeated every minute for five doses. After half a minute the fish made snatches at the air several times in succession, after which it remained in a quiescent state for four and a half minutes, when, after the last ten drops had been administered, it became very excited, and sprang about as if greatly distressed. But it soon sank down, and rapidly "became more and more comatose, until at the end of thirteen minutes from the commencement of the experiment it was in a perfectly motionless state, and in that condition was thrown into a tub of cold water, the fluid being only two inches deeper than the height of the body of the fish lying flat. Here it remained on its side (only jumping up once), giving out bubbles of air, and moving its pectoral fins backwards and forwards, at first rapidly and then gradually slower and slower, until its death, which occurred 27| minutes from the commencement of the experiment. There was no movement of the gills whatever ; and immediately after death the chest was opened, and the heart was not found pulsating, but full of very dark blood; on being touched it contracted sluggishly. Experiment No. 11.-Wishing to collect some of the air contained in these receptacles, a specimen was held under water, and by means of pressure on the superior branchiae all the air was discharged. Each time the operation was repeated the fish, immediately on being released, ascended to the top and took in a fresh supply of air; and the same thing occurred when it was held in the hand and lifted out of the water. In each instance after this aerial respiration air was found in the previously emptied cavities. When these fish are feeding, small bubbles of air are almost invariably discharged through the mouth, probably from the cavity, each time they swallow and they arise almost immediately to inhale more. Experiment No. 12.-A number of these fishes were placed in a tub with a small amount of water and plenty of common grass. No other food was allowed them; but at the end of three weeks thev were perfectly well and lively. * Before drawing attention to the conclusions to be deduced from these phenomena, it may be as well to refer briefly to the opinions previously advanced by others. Commerson considered the labv nnthiform cavity in the Osphromenus intended for the D U T O O SM of smell, and therefore named it Osphromenus, and the species was |