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Show 1870.] INTRODUCTION OF SALMON INTO TASMANIA. 21 bright sun shining, a tent was erected over the gravel-beds, the temperature of the water in which was found to be 55° Fahr. Ice was then freely placed in the transverse open trough at the upper end of the gravel-beds and the temperature thus reduced to 44°. About four o'clock on Thursday, the 21st of April, the first box of ova was opened, and, to the dismay of Mr. Ramsbottom, a very large proportion of the eggs were dead ; but in the second and third boxes affairs looked more hopeful, and by the time a dozen were unpacked it was manifest that a large proportion would be saved. In unpacking, as soon as the lid of each box was unscrewed, the top layer of moss was quickly removed, and the lower layer of moss with the ova was then lifted out, and at once turned upside down on to the cool water running over the gravel-beds. By this means the ova soon separated from the moss, and distributed themselves amongst the gravel, after which the moss was carefully removed bit by bit. The unpacking was continued by candle-light through a great portion of Thursday night, and was renewed at daylight on Friday morning. By Friday night the last of the boxes were finished, and Mr. Ramsbottom calculated that about 35,000 living and healthy ova were safely deposited. Of these, only about 300 were Trout-ova, which were placed in a separate gravel-bed constructed on purpose and closed at each end by perforated zinc. The percentage of living ova varied greatly in the different boxes; but the largest number were invariably found in the boxes in which the ova were more thinly scattered amongst the moss, and had been subjected to only just enough pressure to keep them steady. During the unpacking on Thursday night several living ova were unavoidably picked out and left in the heaps of damp moss beside the gravel-beds through the night. On searching the heaps of moss on Friday morning, several ova were recovered from amongst the moss, and one or two from the stones underneath, and transferred safely to the water. Bedded in the moss of one of the boxes an English Wasp was found, which evinced slight signs of animation. On placing the insect in the sun for a few minutes it became quite lively and walked quickly away. It is true that wasps are scarcely desirable subjects for acclimatization, but surely this circumstance ought to teach us a useful practical lesson as to introducing valuable insects and other similar organisms, especially in their embryonic stages. A few of the boxes of ova had been placed in the vaults of the Wenham-Lake Ice Company for six weeks before the ' Norfolk ' sailed ; and in these boxes, though a larger percentage of ova were dead, the eyes of the fish were distinctly visible in those which were livino*, the development of the embryo having reached a higher stage. Before the whole of the ice was used up, the temperature of the water of the river Plenty fell to 42°, and averaged about 47° for some time afterwards. The only object in cooling the water with ice at first was to prevent the transition of temperature being too sudden. For several days after the deposition of the ova Mr. Ramsbottom was busily engaged in removing all dead ova and pieces of |