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do those of fresh waterforms. The eggs of the herring normally 
incubate in about three or four weeks, but the escape of the 
_young can be considerably delayed by keeping the water very 
cold, while its saltness or the reverse exercises no appreciable 
difference. In the Baltic the German Fish Commissioners 
found that with the water at 53 degrees the eggs hatched in a 
week, whereas with the temperature of the water at 38 degrees 
they took six weeks. In the eggs of the cod fish the American 
_ Fish Commissioners observed that hatching took place between 
_ the thirteenth and fifteenth days, according to the temperature 
of the water, while Sars, in Norway, found some to hatch on 
_ the eighteenth day. The eggs of the haddock in the United 
_ States required an average of nine days, and the shortest period 
observed was eight days, while those of the coal fish (Gadus 
pollachius), hatch in four or five days in water of moderate 
_ temperature. But if we can find such a difference in the cod 
_ family as to the time required for incubation to be from four 
or five days to six weeks, still greater variations are perceptible 
among those of the salmon family. At Howietoun the eggs of 
_ the smelt Osmerus eperlanus) kept in the trout-hatching house 
took about forty-two days; but, on the water being a little 
q warmer, they came out by the thirty-fourth day. In the same 
establishment, with the water kept at about 44-1 deg., the 
_ brook and other trout took from seventy-one to seventy-two 
days; the American charr (Salmo fontinatis) seventy-three ; 
and the salmon seventy-seven. But the foregoing are subject 
_ to wide variations of time (by decreasing the temperature of 
_ the water) as of the trout up to 114 days, and the hatching of 
_the salmon has been delayed to the 145th day, or even more, 
and acting upon this knowledge the eggs of members of the 
Salmonide have been transmitted in safety to the Antipodes. 
‘The eggs of the grayling (Thymallus) normally hatch from the 
twelfth to the fourteenth day. Here I would draw attention to 
the various attempts which have been made to prove that 
salmon can breed in salt water, a proposition advanced by 
some estuary and shore fishermen, apparently in order to show 
tl at there is no necessity to have any restrictive legislation on 
