808 



SCANDINAVIAN FISHKS. 



R. Ir. 3; 11. — ^; A. — ,; P. ^~ : F 



S"— 9 14— 16' 16—17 



9 — 10 



C. X + 1 + 17 + 1 + x; L. lat. 42—46; L. tv. 1. 



4 — 5 



8—9' 



S'jn. Bliccopst's Bugijenhagii, p. p. Heckel, 1. c. (uec Bi,och); 

 QvEXNERSTEDT (Ci/priiius), Ofvers. Vet.-Akad. Forli. 1877, 

 No. 7, p. 13, tab. VII et VIII; Maui {Abramidopsis), Gbgs 

 Xaturh. Mus. Arsskrift, III (1881), p. 25. 



Abramis abramo-rutihis, p. p., Holandbe, Fne Mos., vide Sied. 

 (Bliccopsis), Susswasserf. Mitteleur., p. 142. 



Bliccopsis erijlhrophthalmoides, Jackel, Fisch. Bai/., Abli. Zool. 

 Miner. Ver. Regensburg, H. 9 (1864), 11, p. 49. Hybrid 

 between LeuciseiiR erytlirophthalinus and Aliraniis blicca, 

 Gthh, Cat. Brit. Mtis., Fi.s!,., vol. VII, p. 233. 



The hybrid assumed on the above grounds to exist 

 between the White Bream and the Rudd attains in 

 .Sweden a length of at least '27 cm., including the whole 

 caudal tin. It has the convex dorsal margin of the 

 Rudd — though the dorsal in'otilc, as in the White 

 Bream, forms a sharper break at tlie occiput — the 

 broad forehead of tlie Rudd — the breadth of the inter- 

 orbital space sometimes about 45 % of the length of 

 the head — and the comparatively low dorsal fin of the 

 same species — the length of the longest ray less than 

 '4 of that of the body. But the length of the anal 

 fin, which at least exceeds l(i % of that of the body, 

 at once shows, apart from the number of the rays, that 

 the fish cannot be referred to this species. The pha- 

 ryngeal bones and teeth are also most like those of the 



Rudd; but the only essential difference in this respect 

 between the Rudd and the White Bream lies in the 

 more elongated form of the teeth, with longer and more 

 lateral masticatory surface, and their more distinct 

 pectination in the former. In the only specimen of 

 this hybrid whose pharyngeal apparatus we have been 

 abl(! to examine, the teeth numbered 3, 5 — 5, 3. 



In Sweden, as far as we know, this hybrid has 

 been found only at two localities in Scania and one in 

 Blekinge. It was iirst taken in 1864 l)y Prof. Berg- 

 GREN in Lake Ring; but Prof. Qvenneu.stedt was the 

 first (1876) to notice and determine this find, describing 

 at the same time two other specimens from the same 

 locality, one procured through Berggren, the other 

 taken liy Prof. Naumann, who has also presented a 

 specimen to the Museum of (jothenburg. In the mean- 

 time (1869) a specimen denoted by Qvennersteot (1. c, 

 p. 21) as 'Ex. r, had been caught in the River Helge, 

 and stuffed by Mv. Svensson for the Museum of Kristian- 

 stad. The original of our figure was taken at the be- 

 ginning of May, 1876, by Mr. Lundberg, Inspector of 

 Fisheries, among a haul of Herrings caught in a seine 

 off Lagervik at Karlskrona. According to (^vennerstedt 

 two more specimens have been found in Lake Ring, but 

 not preserved, so that in all 8 examples have hitherto 

 been met with in Sweden, most of them in fresh water, 

 but one in the brackish water of the Baltic island-belt. 



Sometiines 7, according to Fatio. 

 Sometimes 12 — 15, according to Fatio. 



