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Then we have hybrids between the salmon and the trout. 
Here it seems probable that the offspring will be sterile, at 
least such has been found to be the case in the few instances 
- examined at Howietoun. Without detailing all the experi- 
ments which are still in progress, I will advert to a few results 
which have been ascertained. In December, 1881, 20,000 
Loch Leven trout eggs were fertilised by salmon milt, and on 
March 18, 1884, 212 fish, the largest six being each above 
10 ins. long, were transferred to the Octagon Pond at Craigend. 
In November, 1883, 4,500 eggs of the Loch Leven trout were 
- milted from a parr salmon which had been raised at Howietoun. 
_ Most of the eggs hatched, but all the young were deficient in 
vitality, and suffering from dropsy of the umbilical vesicle. At 
the same time 3,695 eggs of an American charr (9. fontinalis,) 
were milted from another salmon parr, but only a few hatched, 
_ seven being alive on my visit in March. A charr, it must be 
remembered, is further removed in relationship from the salmon 
than is a trout, and has smaller eggs. The next experiment 
was made with 1,000 brook trout eggs, milted from a salmon 
parr which had been dead some hours, but none of the eggs 
were vivified, another proof of the deficiency of power in the 
—milt of such young parents. 
In November, 1882, Loch Leven trout eggs were milted from 
American charr, and American charr eggs were milted from 
Loch Leven trout. The result has been a very large per- 
centage of monstrosities, deformities, and deaths, and although 
between 200 and 300 are still alive, the cross does not appear. 
to be satisfactory. 
_ In November, 1882, 9,000 eggs of an American charr were 
milted from a Scotch charr, and neither monstrosities nor 
deformities resulted; ninety-one fine little fish thus bred are 
at Howietoun. In November, 1883, this cross was again made, 
and about 500 alevins are alive and well; and in December 
more were laid down, and upwards of 100 young are preseut. 
Appearances would go to the conclusion that these two forms 
of charr are merely varieties of one species, differentiated in 
colour and by the localities where they live. In short, young 
