8 
SCANDINAVIAN FISHES. 
longitudinal folds underneath, and starting from the 
intermaxillary, forms with the under lip a distinct 
corner at each side of the mouth. A broad flap hangs 
on either side of the under lip. This formation of the 
mouth gives it some resemblance to a swine’s snout, 
and is the origin of the name Berggalt (»rock-boar»), Berg- 
gylta, etc. The cavity of the mouth is narrow, and 
has palatal curtains (transverse folds or vela) above and 
below which are opposite each other and seem intended 
to prevent the escape of water or food through the 
mouth in the act of breathing or swallowing. The 
tongue is thin, and at the tip flat and attenuating. 
When the mouth is open, the upper jaw projects con- 
siderably, as the long nasal processes of the inter- 
maxillary bones glide forward on the ethmoidal and 
frontal bones. In both jaws there is a row of small, 
conical teeth, largest in front and gradually diminish- 
ing in size as they recede on either side. Within this 
row in the anterior part of both jaws is a row of 
much smaller teeth which project very slightly or are 
concealed by the gums. There are no other teeth in 
the mouth itself, either on the tongue, the palatine, or 
the vomer; but in the pharynx there are two small 
upper pharyngeals (each composed of three bones), 
which articulate with the bottom of the skull, and one 
trilobate lower pharyngeal, all three densely set with 
small, obtuse, conical teeth. The eyes are circular, and 
their diameter is from 1 / 5 to 1 /' 7 of the length of the 
head. They are placed fairly high, their inferior edge 
being above a line drawn from the apex of the upper 
jaw to the middle point of the tail. The nostrils are 
small, and have two distinct openings on each side, 
the anterior being prolonged into a dermal canal with 
widened mouth. The sides of the head are covered 
with scales, with the exception of the preoperculum 
itself, the edge of the preoperculum and the anteorbital 
region. It is true that in mature specimens the edge 
of the preoperculum is not apparently denticulated, but 
on taking away the skin one finds on the bone itself 
fine serrations, which are also indicated by some narrow 
strips of skin originating in the middle of the edge. 
In younger specimens the whole edge of the preoper- 
culum is sometimes sharply and clearly crenulated, a 
fact which has caused such specimens to be regarded 
as a distinct species, under the name Crenilabrus multi- 
dentatus. The operculum is large, its depth is greater 
than its length, and the posterior margin forms two 
corners and is continued by a flap of skin which runs 
out into a fine point at the loiver corner. The inter- 
operculum is also large and distinctly visible under the 
preoperculum; it has some scales on the posterior portion 
in the top corner. There are 5 branchiostegal rays, and 
the branchiostegal membranes are united by a, thick in- 
tegument which hangs quite free round the breast and 
is attached to the isthmus only by its front point. 
The body is oval and laterally compressed; it is 
completely covered with large imbricate scales, which are 
thin, have an entire edge and are not marked exteriorly 
with any large streaks. The lateral line is generally 
composed of from 42 to 44 comparatively small scales 
pierced by a horizontal tube, which are not contiguous 
but separated by the scales of the two nearest rows. 
It is consequently not very distinct, and it runs parallel 
with the curve of the back as far as the extremity of 
the dorsal fin where it makes the same downward curve 
as the dorsal line. Above the lateral line there are 6 
or 7 rows of scales and below it 13 or 14. The vent 
is a little behind the middle point of the body. 
The dorsal fin commences just over the base of 
the pectoral fin and ends in a sharply rounded corner 
just where the back slopes towards the tail. At first 
its edge is slightly convex, then somewhat concave, 
rising again at the beginning of the soft-rayed portion. 
Its anterior part generally consists of 19 or 20 spinous 
rays bet ween which the membrane is serrated at its 
edge and prolonged behind each ray except the last 
into a long, lancet-shaped flap. In the posterior part 
are 10 or 11 branched and articulated soft rays, the 
first of which however is, as a rule, simple at the point, 
while the last is divided to the base, apparently forming 
two separate rays. In the anal fin there are 11 or 12 
rays, the first three of which are short and spinous, 
the others longer, soft and articulated. Behind each of 
the first two spinous rays the fin membrane is serrated 
as in the dorsal fin. In the same way the first soft 
ray of the anal fin is often simple, while the last is 
always deeply cleft. The fin is rounded at its extremity 
like the dorsal fin. In length it is about V 7 of the 
total length". The pectoral fins are thin, with distinct 
rays and rounded point; they consist of 15 rays, the 
first of which is short and, like the next ray, undivided 
at the point; the others are branched and thick. The 
a The relative length of tire base of the anal fin diminishes with age. In G measured specimens it was on an average 13.7 % of 
the total length; the minimum was 12.4 %, the maximum 14.5 %. 
