NATURAL HISTORY OF BRITISH SALMONIDA. 163 
as it is situated directly below an almost perpendicular cliff, at 
the base of which it forms a sort of lynn or caldron. In some 
parts it is very shallow, but in others the water is black, and 
apparently of immense depth. 
To the trout of Carraclwddy pools, near Rhayader, has 
been attributed the singular propensity of croaking—indeed, the 
‘croaking trout of Carraclwddy pools’ are regarded as amongst 
the local lions. A writer who visited the pools some years ago 
as an investigator avouches the croaking. ‘When first taken,’ 
he says, ‘and even after they have been in the basket for some 
time, they do decidedly utter a peculiar croak, which the natives 
attribute to their having been bewitched by the monks of 
Strataflorida Abbey ; others again assert that it isan attempt 
to speak Welsh!’ Owing to the colour of the water which 
filters through the peat these trout are nearly black. 
Instances of such varieties might easily be multiplied, but 
whenever there can be any reasonable doubt as to their specific 
distinctions I am all for simplifying rather than for complicating. 
The fewer unnecessary species that are created by ichthyologists, 
the more chance has ichthyology of becoming generally popular, 
especially amongst fishermen. 
In regard to each of the two admittedly distinct species— 
Salmo fario and Salmo ferox—a few general observations will 
probably enable the reader to distinguish them without the 
necessity of resorting to a minute comparison. 
We have not in the present case the same prominent 
differences in the teeth, shape of the gill covers, &c., by which 
the migratory trout and salmon are so clearly defined, and for 
ready points of distinction we must rely upon colour, external 
proportion, and localities; these however will generally be 
found sufficient for the purpose. Thus: 
The common yellow trout breeds indifferently in brooks, 
rivers, and lakes, whilst the great lake trout is never found 
except in or close to lakes (generally large and deep). 
The common trout is almost always spotted over the body 
with crimson, the spots in the great lake trout being in each 
case surrounded by a paler ring, sometimes of a reddish hue. 
M2 
