Salmonidz 331 
usually edged with bright colors. The sexual differences are 
not great. The scales, in general, are smaller than in other 
Salmomde, and they are imbedded in the skin to such a degree 
as to escape the notice of casual observers and even of most 
anglers. 
“One trout scale in the scales I'd lay 
(If trout had scales), and ’twill outweigh 
The wrong side of the balances.’-—LoweE Lt. 
The charrs inhabit, in general, only the clearest and coldest 
of mountain streams and lakes, or bays of similar temperature. 
They are not migratory, or only to a limited extent. In northern 
regions they descend to the sea, where they grow much more 
rapidly and assume a nearly uniform silvery-gray color. The 
different species are found in all suitable waters throughout the 
northern parts of both continents, except in the Rocky Moun- 
tains and Great Basin, where only the black-spotted trout 
occur. The number of species of charr is very uncertain, as, 
both in America and Europe, trivial variations and individual 
peculiarities have been raised to the rank of species. More 
types, however, seem to be represented in America than in 
Europe. 
The only really well-authenticated species of charr in Euro- 
pean waters is the red charr, salbling, or ombre chevalier (Salve- 
Fic. 241.—Rangeley Trout, Salvelinus oquassa (Girard). Lake Oquassa, Maine. 
linus alpinus). This species is found in cold, clear streams in 
Switzerland, Germany, and throughout Scandinavia and the 
British Islands. Compared with the American charr or brook- 
trout, it is a slenderer fish, with smaller mouth, longer fins, 
and smaller red spots, which are confined to the sides of the 
