246 
SAMLET, OB PARK. 
against these it was urged that it must be held uncertain 
whether the roe thus removed had all been shed by the same 
species; and also whether the strange, and perhaps unnatural, 
circumstances in which they had been placed, and which Mr. 
Shaw allows to have been different so far as the important 
point of temperature was concerned, and probably as regturded 
food also, may not have materially influenced the subsequent 
appearances and habits. And these doubts will appear to be so 
much the better founded, since from some of these experiments 
it has been concluded that the Sea Trout and Bull Trout are 
the same species with the Salmon; the contrary of which is 
admitted by every student of nature. 
But this probable mingling of the eggs is not the only, nor 
even the principal cause of the confusion in which the subject 
has been involved. It is known that in the early stages of their 
existence the young of several species of this family bear so near 
a likeness to each other, and especially in what must in this 
case be regarded as the important character of a series of dusky 
bands along their sides, that eminent naturalists have declared 
their inability to distinguish them. It is only at somewhat 
distant periods of their growth, and not by merely an increase 
of size, that specific marks of their individual nature make their 
appearance, and others disappear; and these changes may be 
hastened or greatly delayed through the operation of circum- 
stances, which hitherto appear to have been little understood 
or thought of; and we are again given to see a source of some 
of the fallacies adopted from experiments that have been made, 
by collecting together the young fishes of similar appearance 
in a river, and setting a mark on them by cutting off the 
adipose fin, or punching the gill-covers; with the view of 
ascertaining, not only whether after their migration they return 
to their native stream, to which extent the trial has been 
successful; but also as regards the sameness or diversity of the 
species; in relation to which inquiry the want of discrimination 
at the outset has of course been fatal. 
But whilst these experiments have failed to establish the 
opinion they were at first believed to support, the more earefully 
laboured observations of Mr. Shaw have been trusted to in 
support of the belief, that the fish known by the name of Parr 
is no other than a particular stage in the growth of the Salmon ; 
