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true that these eggs may be hatched with the water being 
changed only once a day, that is not likely to produce vigorous 
fry. At Howietoun there is about one and a half inches of 
water flowing over the eggs, and which does so 160 times every 
twenty-four hours. 
For the purpose of this experiment I was kindly supplied 
from Howietoun with about 500 eggs of the Loch Leven trout, 
averaging 0°21 inch each in diameter; they arrived on November 
28th, about mid-day, having been spawned the previous morn- 
ing from fish in pond No. 11. The eggs were ina cigar box, 
between layers of muslin in damp moss. The railway company 
had subjected the package to rather rough usage, the end having 
been broken while en route. The temperature of the inside 
of the box among the eggs was 50° F., and of the water in the 
hatching trays 45°. Nine of the eggs were removed as dead, 
and three the next day. Having to be absent from Cheltenham 
for five days, the eggs remained unpicked, the supply of water 
however being constantly renewed. On my return, on the 13th, 
the water from the pump had become so thick it could not be 
used, and some clean from elsewhere had to be obtained to 
wash the eggs, which was done with a watering pot. The eggs 
being deposited in the charred boxes, (which had only recently 
been prepared) had their surface covered with the remains of 
the charcoal or charred wood, as well as the mud from the 
pump water, which would evidently be much more probably 
fatal than when glass grilles are employed, for in these latter 
‘there is a space filled with water below the grilles, and although 
mud may be deposited on the top of the eggs, there is generally 
a clear space beneath, where it rests on the interspace between 
two glass rods. Irrespective of this, eggs deposited in flat trays 
are more subject to motion from the current of water than 
they are when laid down in trays in which glass grilles are 
fixed. | 
I do not propose detailing from my daily diary the various 
little mishaps which had to be detected and remedied, but 
some may well be noted, as these remarks are intended mostly 
_ for those who have never practically attended to fish-hatching. 
