CAUl'-FISllES, 



"15 



Fam. CYPRINID.E. 



Air-hhuldcr free {not endowed hi a eapsnle). Mimtli frii/t/ed irith at niofit four (or no) harhels 



The family of the Cypi'inoids, the largest in the 

 whole class of Hshes, contains about 1,UOO described 

 species, most of them, however, from Asia and North 

 America, so that onl}' a lumdred species occur in Europe, 

 and only a score belong to the Scan(lina\ian fauna. 'I'lic 

 majority of our fresh-water fishes are comprised, how- 

 ever, in this family. All the Cyprinoids jjrefer fresh water 

 and are most commonly foinid in lakes, ri\ers, ponds, and 

 fens. Still most of our species also occur in the l)rackish 

 water of tiie Baltic. Not a. single niembi'r of i\\r family 

 is a predatory fisii projierly so called ; most of them live 

 chiefly, though not exclusively, on vegetable substances. 

 They mav with every reason be called omnlrorous. In 

 a certain sense thej' may be regarded as Ruminants: 

 the Carp, the Tench, and the Bream arc adduced as 



18(!9 it was a matter of doubt to what species these 

 eggs belonged. Before this time Krau.ss (18580, Kess- 

 LEH (18(;o'), DviiowsKi (1862'), and Siebold (186;30 

 had described an external ovifei'ous tul)e, sometimes 30 

 mm. long, which in the female Bitterling is developed 

 during the spawning-season from the margins of the 

 urogenital o])ening just behind the vent, and into which 

 the comparatively large, ellipsoidal eggs — sometimes 3 

 ■mm. long — force their way and arrange themselves in 

 a single row. Noll'' at last discovered that the .said 

 eggs in the branchial cavity of the painter's mussel be- 

 long to the Bitterling. By observations which he has 

 since completed, he siiowed that, when the eggs are ri]w, 

 the female Bitterling applies the oviferous tube to the 

 inspiratory opening of the painter's mussel, into which 



examples of this; but as a rule food passes rapidly | the male at the same time emits his seminal fluid. In 



through their intestinal canal: a Goldfish fed with wheat- 

 bread pas.ses after some minutes a white, vermiform mass 

 of excrement, which hangs from the vent. They are 

 sensitive in a high degree to atmospheric influences; 

 but some of them, though they do not properly belong 

 to an Arctic temperature, can in a torpid state survive 

 the process of being frozen". Even in a milder climate 

 they are known in cold weather to collect in dense 

 shoals, which lie still in the deepest parts of the water; 

 and Valenciennes'' states of the liarbel (jf Southern 

 Europe that he once found a company of this species 

 which during the winter had packed themselves together 

 in the hollow trunk of a tree. 



Among the peculiarities in the reproduction of 

 these fishes we shall here remark only one, which is of 

 general interest, but belongs to a species foreign to our 

 fauna, the little Bitterlnig (Rhodeus nninrus), a form 

 fairly i-ommon in I'astern and Central Europe and at 

 most about 1) cm. long. It has long been known that 

 the eggs of some fish are found among the branchial 

 lamellae of the painter's mussel {Vnio putorum): but until 



III. p. -2118 



this way about 40 eggs may be forced one by one into the 

 bi-anchial cavity of the mussel, where they attach them- 

 selves to the branchial lamelLe and are developed until 

 the fry have attained a length of about 11 mm. The 

 young of this flsli thus lead a kind of parasitic life, a 

 commensalism fnjm which they liberate themselves, 

 when capable of an independent existence, bj' making 

 their w-ay out through the expiratory tube of the mussel. 



The spawning-season of the Cyprinoids occurs in 

 spring and summer, when both sexes assume a brighter 

 and more handsome dress, and the males develop sharp, 

 tubercular excrescences on the scales, which excrescences 

 fall off, however, simultaneously with the fsiding of the 

 coloration, as soon as the spawning-season is over. 



To man these hshes are of no inconsiderable value 

 and utility. Most of them have a soft, white, and pa- 

 latable flesh, and in Scandinavia, as on the Continent, 

 are the objects of lucrative fisheries. This is not the 

 case in England, \\'here fresh-water fishes in general are 

 little esteemed", and the Cyprinoids in particular (with 

 the exception of tiie Carp) have a bad reputation. 



" P.\LLA.s (of the Crucian Carp), Zoogr. lloss. Asiat., ton 



' Ccv., Val., Hist. Nat. Pois.i., torn. XVI, p. 1.3. 



' .Jahreshefte d. Ver. f. vaterl. Xaturk. in Wiirtteniberg, 14 .Jaliig., p. 121. 



'' At the Conference of Naturalists at Konigsberg. according to Siebold. 



' Cyprinoiden Livlands, p. 87. 



■' 6'usswasserrisclie Mitteleuropas, p. 118. 



^ Zoologischer Garten 1869, p. 257; 1870, p. 237; 1877, pp. 351—362. 



'' Day lays tlie blame of this on the English cook's ignorance of the pro]ier nietliod of dressing fresh-water tish for table. 



