762 



SCANDINAVIAX FISHES. 



are simple, the tirst t)eing hardly perceptible externally", : small. Tliey are imbricated, and lie in distinct series, 



the third the longest ray in the whole fin, or equal in They are uf a rounded (juadrilateral form, but the two 



length to the fourth. The last seven rays are repeatedly anterior corners are generally well marked and separ- 



branched at the tip, and the last ray is cloven almost ated by sinuses from the middle of the anterior margin, 



to the base. which is convex and crenulated by tliree or four small 



'I'lie anal fin is of nearly the same shape as the undulating sinuses, into which the grooves'' radiating 



dorsnl, and of exactly the same structure, except that forward from the central rnicieus open. The posterior 



it has an additional branched ri\y. Its corners, espe- (free) part of the scale contsiins from two to nine such 



■ially the posterior, are more pointed, and the margin 



grooves, more or less distinct. The lateral line descends 



is slightly concave. The fin begins at a distance from I at first, and then runs (fi"om about the middle of the 



the tip of the snout that measures on an average some- i abdominal region) parallel to the ventral line and nearer 



what less than ^3 (varving in our specimens between t to the belly than to the back. The" iuanl)er of scales 



63 and 66'/, ^) of the length of the body, and its base | in the lateral line (ab(jut 52 in Dace from the north) 



occupies on an average about ' ^ (vai-ying in our spe- 

 cimens between 8'9 and 9"8 %) of the same length. Its 

 iieiglit is on an average about '/^ (varying in our s])e- 

 cimens between 12 and 13 %) of the length of the Iwdy. 



riie pectoral fins are oblicjuely 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. Tlie ventral fins, on the other hand, nre 

 broader and more rounded, and are furnished on their 

 front (outer) side, as usual in this family, with two 

 simple ravs, so closely united that the first is not al- 

 ways distinguishable. Their length measui'es in young 

 specimens about 14 %, m old about 12' 2 ?* 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 '/'j (varying in our specimens lietween 

 23V2 and 28 %) of the length of the body. The di- 

 stance from the former point to the ti]) of the snout 

 varies between about 44 and 48 % of the length of the 

 body, and to the beginning of the anal fin lietween 

 about 20 and 21' . % of the same length. Tiie bases 

 of these fins are furnished as usual with a ])ointed, 

 lanceolate appendage. 



The caudal fin is foi-ked, with lobes of equal length, 

 its middle ra}'S occuyjy about 8— 7 "a of the length of 

 the bod}-, aiul are less than ',.,, sometimes only '/,,, as 

 long as the longest rays. 



The scales which cover the bodv, are of moderate 



is the greatest possessed by any Scandinavian Leiicisciis 

 except the Ide. The said number would thus give us 

 the most easily api)licable 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'. 



The coloration shows great resemblance to that of 

 the kindred species; but the colours of the Dace are 

 palei-, less diversified, and not so bright. Tlic 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 spaw-ning-season. The iris 

 is silverj' with a dash of yellow and a narrow ring of 

 deeper vellow next the pujiil; it is finely punctated with 

 green pigment, and has a dark, curved band at the top. 

 The sides of the head are silvery \vith a strong tinge 

 of vellow, and shade into various colours. The dorsal 

 fin is plain, pale grayisli brown, the caudal tin bright 

 olive green, and all the lower fins ])ale Avith 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 alidominal cavitv, 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 



size, but in comparison with those of the Koacii rather , Siberia, where the species has been ft 



ordini 



" Artedi overlookfil tlic tirst, sliorl ray, but comili'c] tlir last, deeply cloven ray twice over, thus arriving at tlie correct number of 

 rays in the dorsal fin. 



' The number of these grooves is generally about 1 1 ; but on the caudal scales they may be much more numerous, as many as 

 though only a few, about 9, extend to the nucleus of the scale. 



<■ Jeitteles. Fisflie dn- .Vnrrh bei Olmiit:. II Abth., pp. 1.1 and ICi. 



