946 



SCANDINAVIAN FISHES. 



SrDJS ATLAXTICUS, 



which was found dead in May, 1865, where it had 

 been cast ashore near the Skaw. Two specimens are 

 said to ha\e been observed, after a violent storm from 

 the west; but only one was secured, and this reached 

 Kuoyer's hands in a greatly damaged condition. It 

 was a large fish, half a metre long, with much deeper 

 body than the other known species of the genus. The 

 greatest dejjth was contained only 7 times in the length 

 of the body. A manuscript published in part by LCt- 

 ken" after Kroyer's death further contains the remarks 



that the length of the head was 21 "7 % of that of the 

 body, that the dentition of the mouth was compara- 

 tively feeble and uniform, that the articulation of the 

 lower jaw lay nearer to the perpendicular from the 

 anterior margin of the eye than in the Greenland form, 

 Sudis borealis, that the ventral fins were situated below 

 the true dorsal fin, that the adipose fin was compara- 

 tively remote from the caudal, that the pectoral fins 

 contained 15, the anal fin 20 rays, and that the scales 

 were small, numbering about 20 in a transverse row. 



Fam. CLUPEID^. 



Body of the well-known Herring form, hut more or less deep or elongated, more or less terete or compressed. Scales 

 middle-sized or small, thin, and generaUy deciduous. No luminous spots on the sides of the body. No adipose 

 fin. Margin of the upper jaw formed, hy the intermaxillaries in front and by tlie maxiUaries behind. No bar- 

 bels. Air-bladder simple or internally cellular; its communication trith the cranial cavity, where such a commu- 

 nication exists, without mobile osseous connexion. Branchial cavity usually furnished with large pseudobranchia. 



Ovaries furnished n-ith oviducts. 



No ])iscine familv is so important to man from an 

 economical point of view as the Herrings; and for the 

 systematist too this family possesses great interest. 

 Around it are grouped a number of families, foreign 

 to the Scandinavian fauna, that combine its characters 

 not only with preceding ty])es, but also with Ganoid 

 peculiarities. Soon after Muller, on the strength of 

 Vogt's investigations, had referred the genus Amia to 

 the Ganoids', where Agassiz" had previously ranged 

 Lepidosteus and Polypterus, which forms as M'ell as 

 Amia Cuvier'' included among the Herrings, Stannius' 

 sho^ved that the character upon which Muller had laid 

 special stress, the double row of valvules at the passage 

 from the ventricle of the heart to the bulbus arteriosus, 

 also appears in liufirinus {Albula), another of Cuvier's 

 Herring-fishes, which is still referred by some authors 

 to that family. Gegenbaur' showed — a thought which 



had suggested itself to Mulli:i! — that the most essen- 

 tial difference in this respect Ijetween the Teleosts and 

 the Ganoids together with the true cartilaginous fishes 

 consists in the following circumstance. In the latter 

 the ventricle of the heart, with the transversely striped 

 muscles of its wall, is prolongated forward to a tubu- 

 lar, more or less conical chamber {conns arteriosus), 

 on the inner surface of which the valvules in their 

 more or less numerous rows are situated; whereas in 

 the Teleosts the heart is destitute of this prolongation, 

 the beginning (base) of the branchial artery that issues 

 from the ventricle being instead dilated into a bulb 

 {bulbus arteriosus), without muscles (with only elastic 

 wall) or with unstriped muscles alone in its wall. 

 Stohr' completed these observations by pointing out 

 the structure and disti-ibution of the rows of valvules 

 in different (Tauoids, Sturgeons, Chimajras, and true 



" Vid. Meddel. Natiirh. For. Kbhvn 1891, p. 231. 



' Abh. Akad. Wiss. Berlin 1844, p. 204. 



' Recti. Poiss. Foss., torn. II, part. II, p. 1. 



■' Begjie Animal, ed. 2, tom. II, pp. 327 — 329. 



"■ Beinerkungen ilber das Verlialtniss der Ganoiden :u den Chipeide 



J Jen. Zeitschr., Bd. 2 (1866), p. 365. 



1 Morphol. Jalirb., Bd. 2 (1876), p. 197. 



Kostoek 1846. 



