SALMON. 
855 
ed, conical shape; but in old males this process is 
accompanied by a depression in front, the intermaxil- 
lary bones being parted from each other, and the me- 
dian region of the pramasal part being hollowed under- 
neath or even perforated, to receive the tip of the 
hook simultaneously formed by an upward growth of 
indurated connective tissue from the point of the lower 
jaw. These old males are known in popular language 
by the name of kroklaxar (Hook Salmon, the French 
becard, Salmo hamatus, see above). 
Not only have these males with their singular 
snout — the function of which is not yet known" — 
been regarded as a distinct species, but the same rank 
has also been conferred, for their short snout and pe- 
culiar coloration, on the two stages of growth follow- 
ing next after the fry, the Parrs ( Salmo salmulus ) and 
the Foreller or so-called Common Trout ( Salmo fario ). 
Even in early youth the ground-colour of the 
Salmons varies according to the colour and light of 
their environments. v. Wright’s figure (Plate XL, 
fig. 1) represents a young specimen some months old 
as it appears during the assumption of the dress which 
is more fully developed in the Parr stage. 
The dress of the Parrs is described at length by 
Fries (1. c.), from the coloration of the Salmon fry in 
Norrkoping River: “The top of the head and the back 
are olive-green, with dark, round, stellate spots and 
patches along the back. These small, dark spots ex- 
tend in front down to the lateral line; but from the 
neighbourhood of the dorsal fin to the caudal they 
terminate half-way between the dorsal edge and the 
lateral line. The belly is white with a dash of yellow. 
The sides are of a handsome light yellow shading 
into red. Along the lateral line lie 8 or 9 small, 
round orange spots and the same number* of large 
and oval, bluish patches, set transversely and crossed 
half-way up by the lateral line. These patches (the 
so-called Parr markings) alternate with the orange 
spots'’. Above each eye is an arch of 4 round, dark 
spots, and further back, between these arches, are 3 
similar spots, set in a triangle; but all these markings 
may be more or less distinct, and they show some 
variation. Very constant, on the other hand, are the 
two round, black spots that adorn the gill-covers, 
though their size and position vary. In most cases 
one of them is situated at the centre of the operculum, 
the other in front of the preoperculum, just behind 
the eye. Sometimes traces of a third spot may be 
detected at the very margin of the operculum. The 
dorsal fin is of a light olive green, with one distinct 
and one less prominent and irregular row of dark spots, 
the former at the bottom, quite near the base and 
parallel to the back, the latter along the middle of the 
fin. The anterior corner shades into flame-yellow, 
marked off by a dark gray band, which starts from 
the tip of the second simple ray and runs in a straight 
line to that of the fourth branched ray d . The adipose 
fin wears the olive-green colour of the back, with yel- 
lowish tip. The caudal fin is olive-green, tinged with 
yellow, edged with flame-yellow above, below, and, 
less distinctly, behind. The anal fin is of a dirty yel- 
low, with the outer part of the anterior margin lighter, 
and with an indistinct gray band obliquely across the 
anterior corner. The pectoral fins are olive-green with 
a darker band across the middle. The ventrals are 
similar in colour and markings to the anal fin. The 
pupil is rounded and very large in the living fish, buf 
after some exposure to the atmosphere it assumes a 
triangular shape. The flesh is white, without red 
tinge.” 
During the Forell stage the two varieties differ 
more widely from each other, for the young Salmon 
make their way to the sea as early as possible, and 
when this instinct begins to awaken, they gradually 
° Many conjectures have been made on this head. Some have supposed that the hook is a kind of spade or thrusting apparatus to 
he used in working holes to receive the eggs. But, so far as is known, the female is at least more active than the male in this operation. 
Others have thought it to be a hook with which the male holds the female fast while spawning. But the most trustworthy observers have 
seen the spawning performed without its assistance. Others, again, have suggested that it is a protective organ, to prevent the males from 
inflicting too severe injuries on their rivals in the breeding-season. But such means of protection seem far from natural. The least violent 
explanation appears to be that the hook is an essentially pathological appearance, characteristic of age, but produced by the irritation caused 
by blows on the snout, both during combats and in leaping over obstacles. 
b Sometimes, however, ns many as 15. 
c The ground-colour of the sides generally, grows lighter round the Parr markings, at least along their lower margin, thus rendering 
them still more prominent. 
d Cf. the analogous marking (the corner pure white and the stripe black) on the dorsal fin of Trout Parrs, according to Jardink, 
British Salinonidce, pi. XI. 
10S 
Scandinavian Fishes. 
