762 
SCANDINAVIAN FISHES. 
are simple, the first being hardly perceptible externally a , 
the third the longest ray in the whole tin, or equal in 
length to the fourth. The last seven rays are repeatedly 
branched at the tip, and the last ray is cloven almost 
to the base. 
The anal tin is of nearly the same shape as the 
dorsal, and of exactly the same structure, except that 
it has an additional branched ray. Its corners, espe- 
cially the posterior, are more pointed, and the margin 
is slightly concave. The tin begins at a distance from 
the tip of the snout that measures on an average some- 
what less than 2 /a (varying in our specimens between 
63 and 66 V 2 %) of the length of the body, and its base 
occupies on an average about 1 j 11 (varying in our spe- 
cimens between 8‘9 and 9'8 %) of the same length. Its 
height is on an average about Vs (varying in our spe- 
cimens between 12 and 13 %) of the length of the body. 
The pectoral tins are obliquely pointed, and con- 
sist of 1 simple and 17 or 18 branched rays, of which 
the last (lowest) two or three are small and difficult to 
distinguish. The ventral tins, on the other hand, are 
broader and more rounded, and are furnished on their 
front (outer) side, as usual in this family, with two 
simple rays, so closely united that the first is not al- 
ways distinguishable. Their length measures in young 
specimens about 14 %, in old about 12 1 /, * of that of 
the body. The distance between the foremost (outer- 
most) point in their insertions and the corresponding 
point in the insertions of the pectoral fins is on an 
average about 1 / i (varying in our specimens between 
23V 2 and 28 %) of the length of the body. The di- 
stance from the former point to the tip of the snout 
varies between about 44 and 48 % of the length of the 
body, and to the beginning of the anal fin between 
about 20 and 2 1 1 2 % of the same length. The bases 
of these fins are furnished as usual with a pointed, 
lanceolate appendage. 
The caudal fin is forked, with lobes of equal length. 
Its middle rays occupy about 8— 7 % of the length of 
the body, and are less than 1 /' 2 , sometimes only 1 / 3 , as 
long as the longest rays. 
The scales which cover the body, are of moderate 
size, but in comparison with those of the Roach father 
small. They are imbricated, and lie in distinct series. 
They are of a rounded quadrilateral form, but the two 
anterior corners are generally well marked and separ- 
ated by sinuses from the middle of the anterior margin, 
which is convex and crenulated by three or four small 
undulating sinuses, into which the grooves 6 radiating 
forward from the central nucleus open. The posterior 
(free) part of the scale contains from two to nine such 
grooves, more or less distinct. The lateral line descends 
at first, and then runs (from about the middle of the 
abdominal region) parallel to the ventral line and nearer 
to the belly than to the back. The number of scales 
in the lateral line (about 52 in Dace from the north) 
is the greatest possessed by any Scandinavian Leuciscus 
except the Ide. The said number would thus give us 
the most easily applicable character for the Dace, if it 
were not stated from more southern localities that the 
species may have only 44 scales in the lateral line 0 . 
The coloration shows great resemblance to that of 
the kindred species; but the colours of the Dace are 
paler, less diversified, and not so bright. The top of 
the head and the back are dark olive brown, the sides 
silvery gray and lustrous, with a strong tinge of pale 
ochreous yellow during the spawning-season. The iris 
is silvery with a dash of yellow and a, narrow ring of 
deeper yellow next the pupil; it is finely punctated with 
green pigment, and has a dark, curved band at the top. 
The sides of the head are silvery with a strong tinge 
of yellow, and shade into various colours. The dorsal 
fin is plain, pale grayish brown, the caudal fin bright 
olive green, and all the lower fins pale with a dash of 
yellow, especially at the base. The rays of the last- 
mentioned fins are flame-coloured at the middle, and 
the bases of the ventral fins are of the same hue. In 
young specimens the lower fins are light and quite 
colourless. 
In the internal organs, on examining them within 
the abdominal cavity, we found no essential difference 
from other species. 
The geographical range of the Dace extends over 
the whole of Europe north of the Alps, with the ex- 
ception of Scotland and Ireland, and over Western 
Siberia, where the species has been found, according 
a Artedt overlooked the first, short ray, but counted the last, deeply cloven ray twice over, thus arriving at the correct number of 
rays in the dorsal fin. 
b The number of these grooves is generally about 11; but on the caudal scales they may be much more numerous, as many as 28, 
though only a few, about 9, extend to the nucleus of the scale. 
c Jeitteles, Fische der March bei Olmtitz, II Abth., pp. 15 and 16. 
