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that the water stood about half way up its sides. 10th, 3 p.m., 
one egg looks a little cloudy, but the other is clear. 11th, 
9 p.m., one certainly dead, but a little vitality in the other: 
2.30 p.m., both dead, or 48 hours from the commencement of 
the experiment. 
January 9th, 2 p.m., placed two eggs, under exactly similar 
conditions, in a tumbler of brackish water, of 1008° specific 
gravity. 21st, eggs have been going on pretty satisfactorily, so 
changed the water to 1019°, and so continued it for two days, 
‘and then reverted to 1008°. Feb. 24th, 10 a.m., as they had 
not hatched, they were put into a tumbler of fresh water, and 
brought in-doors, when the temperature of the water rose from 
48° to 60°: at 1 p.m., one of the eggs began to look as if it 
would probably hatch, and at 4 p.m., the young came out. I 
now removed it to another tumbler, and gradually cooled the 
water down, and returned the fish to the tray, where it did well. 
March Ist, 10 a.m., the other egg commenced to hatch, the 
yelk-sac coming first; at 5 p.m., it hatched, and was seen to 
have dropsy of the sac. This little fish was likewise returned 
to the tray, but did not do well; the movements of the heart 
were very languid, pulsations 84 per minute, and under a strong 
glass various congestions were seen in the course of the blood 
vessels as at the upper side of the orbit, but in most parts of the 
body it was very anemic. The clear interspace between the 
yelk-sac and its outer covering was very distinct. It died on 
March 7th. As dropsy of the sac is usually considered a result 
of constitutional weakness, and no other example suffering from 
it, it is reasonable to conclude that such must have been the 
effect of the brackish water in which the egg was kept. 
January 9th, 2 p.m., for the sake of comparison placed two 
trout eggs in a tumbler of fresh water, under the same con- 
ditions as the foregoing, changing the water daily. February 
24th, eggs not having hatched, they were placed in one of the 
hatching trays, on the wooden floor of which they both came 
out in twelve hours’ time. 
January 21st, 10 a.m., placed two trout eggs in salt water, 
at 1019°; 25th, 4 p.m., both were dead, or within four and a 
half days. 
“a 
