THE ORIGIN OF VARIETIES IN SALMONID. 185 
similarly reared there exist no reasons why they should not in a 
like manner differ from the primitive stock. Were such forms 
transferred to ponds or streams they might retain such abnormal 
variation through succeeding generations, or return to what 
normally existed among their progenitors, and thus changes may 
be induced which ought to be regarded as mere varieties, but 
most probably would be looked upon as specific were specimens 
sent to a museum. When a history of the origin of the eggs 
which produced the original stock is required before any 
decision can be given as to what the species is, one becomes 
disposed to question whether species are not being unduly multi- 
plied. It will be exceedingly interesting to watch the Salmo 
fontinalis in this country to ascertain the changes of form which 
occur, and especially to observe whether it does or does not 
interbreed with other species, for although I believe that not 
unfrequently examples of Salmonide@ are erroneously considered 
hybrids, there can be no question but that hybrids may and do 
occur. But in many instances when two of the at present deter- 
mined species interbreed, and the result is a so-called hybrid that 
is not sterile, the possibilities are that the observer has erroneously 
considered as two species what were in reality merely local 
varieties of one. , 
The next fish I will allude to is a young Salmon, which was 
reared by Mr. Frank Buckland from eggs received from Huningen, 
and which were collected from Salmon captured for this purpose 
from below the Falls of Schaffhausen. Examining the specimens 
(there are four), I cannot see how any doubt can arise respecting 
their being the young of the true Salmo salar. As year after year 
passed by, and these fish were retained in the small amount 
of fresh water which was sufficient to fill the tanks in the 
Horticultural Gardens, the same results developed themselves 
which have usually attended keeping Salmon-parr in small fresh- 
water ponds. The body, in short, is that of the Salmo gracilis of 
Couch, and the specimens closely agree with the figures in 
Dr. Murie’s paper, in the ‘ Proceedings of the Zoological Society’ 
for 1870, upon certain irregularities in the growth of the 
Salmon. 
Passing on to the Gillaroo Trout, the question arises, Is this 
a variety or a distinct species? Hunter was fully aware of the 
existence of this fish, and placed specimens of its stomach in his 
