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 unpack- 
ing, 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 fivished, and Mr. Rams- 
bottom 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 ouly 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 in- 
sect 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 
living, 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 sud- 
den. For several days after the deposition of the ova Mr. Rams- 
bottom was busily engaged in removing all dead ova and pieces of 
