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Show 30 MR. F. DAY ON RACES AND [J bound, not a few were sterile, while the number of eggs from those ripe for breeding were, fish for fish, less than in 1882. Taking all things into consideration the time appeared to have arrived when the paying value of most of these Trout had come to an end, and it was decided that they could no longer be kept with advantage. The sluice was therefore opened on November 27th, and the next morning we proceeded to the pond to select such fish as were worth preserving and spawn such as proved to be ripe. On arriving at the pond the water was found to have nearly run down, and in the mud at the bottom were many dead Trout, not short of 100, the majority of which were about two feet in length, some kelts, some egg-bound females, while a few were floundering in the mud. On removing with a net the remaining fish, it was observable that a change in the colour of some had occurred ; and the same change was observed among some of the 1876 Lochleven Trout-namely, that the anal fin had a white edge and the anterior-superior margin of the dorsal fin was also white, thus reverting to the Brook-Trout form of colour. Attention may likewise be drawn to all the hybrids between this form of Trout and the Salmon possessing a white edge to the dorsal and anal fins. Those who consider colour as indicating a specific difference in these fish differentiate the Lochleven from the Brook-Trout by the latter possessing a white edge to their fins, which is deficient in the former. These old and undoubted Lochleven fish are throwing back in colour to the Brook-Trout livery; and likewise among the crosses between this variety and the Salmon we find the white edge to the fins as seen in the Brook-Trout invariably present, although absent from the parents. On placing a net in the ditch into which the island-pond drained, a considerable number of Trout-ova were found in it. Whether these were from the bottom of the pond, or whether an old female had got jammed in the valve and her eggs discharged, it was not possible to say, but they were white and opaque, as if they had been exuded longer than 12 hours. Forty-two large Trout had to be killed as evidently passe', and about 300 of the remainder were removed to another receptacle. The small amount of fertile males was remarkable; while all the old ones had the hook at the end of the lower jaw. Among the fish in this pond were some of the hybrids between the Salmon and Trout, bred from ova taken in November 1879, and already adverted to. On November 15th, 1882, Sir J. Gibson-Maitland in m y presence obtained about 2000 ova from a Lochleven Trout, which were fertilized with milt from an American Brook-Trout, or Charr, Salmo fontinalis. These were placed in hatching-box no. 108, and on November 29th, 1883, about 150 were alive. They had been transferred to a large wooden rearing tank through which a stream of water flowed. The mortality among these 2000 eggs had been as follows:-November 68, December 142, January 89, February 41, or a total of 340 eggs. The young were much malformed, monstrosities being numerous, blindness in both or in a single eye, and bull- |