351 
Willoughby (1686) remarked that he was persuaded that the 
salmon and the various forms of trout interbreed: and many 
authors in this country have erroneously asserted that par were 
hybrids, until the question was set at rest by the fish culturists. 
Mr Shaw, on April 26th, 1841, informed Mr Scope that his 
“experiments with the ova of the common trout and salmon 
had been quite successful, and that the hybrids had hatched, 
and were in good health.” Again, in October, he observed that 
“they were all in a very healthy state, the cross not having in 
the slightest degree affected their constitutions.” 
Edmund Thomas Ashworth (Propagation of the Salmon, 1853, 
page 19) observed that “the ova of trout fecundated by the 
milt of the salmon, by the care of MM. Berthot and Detzem, 
and forwarded from the banks of the Rhine, were hatched in 
their laboratory. Also ova of salmon fecundated by the milt of 
trout gave the same results.” Davy (1858) remarked that it had 
been ‘ascertained that the ova of the salmon can be impreg- 
nated with the milt of the common trout,” and subsequently, 
that “Mr Reynolds mixed together the roe of, the lake trout 
and the fluid milt of the char, which he placed in his breeding 
boxes in November. In seventy days some of the ova were 
hatched.” I received from Howietoun (January, 1885) three 
figures of hybrid Salmonide taken in colours from fish in spirit 
in the “ College of France,” at Paris. The label asserts “ these 
were from Professor Coste’s fish house, 1866-67. The water 
became bad when they were about eighteen months old and 
killed them. They had milt and roe.” 
Professor Rasch in 1867 instituted experiments in order to 
practically test the question of hybrids among the Salmonide ; 
he found that the ova of the sea and river trout were developed 
regularly, whichever form were the parent one, and that the 
offspring were fertile. That of the ova of the char, fertilized 
by the milt of the trout, 30 to 40 per cent. were developed, but 
many young fish perished after being hatched. Trout ova, 
fertilized by the milt of the char, only gave 10 per cent. of 
young, many of which were mis-shapen. Salmon ova, fertilized 
with trout milt, yielded 40 per cent. of young fish, but more if 
