CRUCIAN CARP. 
739 
resemble those of the Lake Crucian Carp; and this ap- 
plies also to the nostrils, though they are sometimes 
set a little higher. 
The scales are like those of the preceding variety 
in form, number, and distribution. The lateral line 
shows some difference, being generally somewhat more 
curved, and lying nearer the back. The position of the 
vent is the same. 
The dorsal fin, which in the number of the rays 
resembles that of the Lake Crucian Carp, is distin- 
guished from the latter by the difficulty which often in- 
volves the detection of the first ray, and which not un- 
frequently causes this ray to be overlooked. In form the 
difference is greater, the dorsal fin of the Pond Crucian 
Carp being always higher in front and less arcuate at 
the margin. The anal fin may lie recognised by its 
somewhat greater height and less rounded anterior cor- 
ner. The caudal fin, even when strongly expanded, and 
even in old and large Pond Crucian Carp, is concave at 
the hind margin. The pectoral and ventral fins of the 
two varieties are alike in all essential respects. The above 
differences in the form of the fins in general range the 
Pond Crucian Carp on a level with young individuals. 
The coloration of this variety is generally darker 
than that of the Lake Crucian Carp. The back is of a 
dark olive green, and the top of the head still darker. 
The dark tint of the back grows somewhat lighter down 
the sides, the inner coat of brassy yellow being more 
distinct here than on the back, where it is often in- 
visible. The belly is dark yellow. The dorsal fin is 
of the same colour as the back; the other fins are gray, 
more or less deeply tinged with red. The iris is brassy 
yellow, but often rendered brown by the dense dots 
with which it is strewn. The pupil, however, always 
has a fine, brassy yellow rim. 
In the structure and arrangement of the internal 
organs there is only one difference: in the air-bladder 
of the Pond Crucian Carp the round anterior part is 
comparatively larger, and the posterior part not so 
sharply curved, shorter, and narrower, a circumstance 
which seems to depend on the stronger contraction of 
the hind part of the abdominal cavity. 
The Crucian Carp, which in Scania and Bohuslan is 
called Karussa (probably from the Danish Karudse ), oc- 
curs almost everywhere in Sweden, even in the District 
of NorrbottenC In Norway and Finland, according to 
Collett and Mela, the northern range of the Crucian 
Carp is about equally great, extending to at least 66° 
N. latC The individuals that occur in these northern 
regions do not, however, attain any considerable size. 
The species seems also to diminish in size towards the 
west, for though even in the District of Gefieborg it 
attains a weight of 3 3 / 4 lbs. (17 hectogrammes), Collett 
mentions a specimen 260 mm. long as the largest Cru- 
cian Carp from the neighbourhood of Christiania pre- 
served in the University Museum of that city; and this 
specimen probably weighed no more than 7 or 8 hecto- 
grammes. In the central and southern provinces of 
Scandinavia the species is extremely common, and it is 
here too that it attains the greatest size. In Wermland 
it is rarer and smaller. The Crucian Carp is also spread 
over the whole of Europe 0 and Central Asia, together 
with Siberia, eastwards to Amur and China. 
a Cf. Underd. Bet. Forsl. Ny Fiskeristadga 1883, Bilaga III, ] 
6 Gkimm ( Fishing and Hunting on Russian Waters 1883, p 
“about 65° N. lat.” 
c Apostolides ( La Peche en Gr'ece , 1883), however, does not 
The favourite haunts of the Crucian Carp are small 
lakes with shallow water and weedy and oozy bottom. 
When it is found in larger pieces of water, as in the 
western island-belt of the Baltic or Lakes Wener, Wetter, 
and Hjelmar, its occurrence is confined to shallow, weedy, 
and muddy inlets. It also thrives well in small ponds, 
peat-haggs, and other collections of stagnant water, and 
is the only one of our indigenous fishes, except the 
Three-spined Stickleback, that is plentiful and multiplies 
freely in such localities, for the Carp cannot be regarded 
as an indigenous Scandinavian species. Hence the Cru- 
cian Carp, like the Carp, is kept in ponds, almost as a 
domestic animal, to supply the wants of the table. It 
can even put up with polluted water. Pallas also tells 
us that the Crucian Carp, which does not even disdain 
the salt water of the steppes, is the first fish to make 
its appearance in new-formed lakes and fens, of which 
fact lie saw instances in the basin of the Isset, a tri- 
butary of the Tobol (Siberia). 
In such small pools, where there is never a suf- 
ficiency of food for any considerable number of fishes, 
. 158. 
. 13) sets the northern limit of the Crucian Carp’s range in Russia at 
include the Crucian Carp among the fishes of Greece. 
