730 



SCANDINAVIAN FISHES. 



Pike-perch are also of service, though not in exactly 

 the same degree. But large numbers of other fishes, 

 especially of the Carp's uwii family, such as Roach, 

 Rudd, or Crucian Carp, only do mischief. The most 

 practical method of keeping the ponds clean, a method 

 which at the same time renders their bottom l)etter ca- 

 pable of developing food for the Carp, is to drain them 

 in turn and leave them dry for a year, during which 

 period they may be plougiied and sown, in most cases 

 with good results. They must also be emptied to faci- 

 litate the transfer of the fish from one pond to the 

 other, an operation which should be performed during 

 the cool season, in autumn or spring, the heat of sum- 

 mer being at best disagreeable to tlie Carp on dry land. 

 It is obvious that the ponds should also be protected 

 from the inroads of poachers, otters, herons, and other 

 enemies of the Carp; but ducks do no damage. The 

 reader who desires fuller information on this head, will 

 find what he needs either in Norback's Handledning i 

 Fiskerdrd ocJi Fiskafvel (p. 257) or in the numerous 

 German manuals on the subject, e. g. Max v. d. Borne, 

 Haudhuch der Fischzucht nnd Fischerei, Berlin 1886, 

 p. 261. 



Among Carp as among other domesticated fishes 

 we frequently meet with deformed individuals. One of 

 these examples, not uncunnnon in its occuri'ence, with 

 the snout apparently reduced, is described by Valen- 

 ciennes". The reduction, however, does not really affect 

 the snout or the jaws, which parts are developed as 

 usual, or only distorted, the frontal bones, on the other 

 hand, being anteriorly depressed, and the basisphenoid 

 and parasphenoid bones reduced. 



In the pond the Carp is a victim to all kinds of 

 diseases. We sometimes hear of Carp being so old that 

 moss has begun to grow on tlieir bodies, this moss 



being reallj^ a mould fungus, Saprohfjiiia, of the same 

 genus as the scourge of the Salmonoids. The best re- 

 medy for this is a little salt in the pond or a change 

 of water. By unsuitable food the whole stock of a pond 

 may be jjoisoned. Carp may l)e fed and fattened on 

 ordinary kitchen-refuse, bi'ewer's grains, ])oiled and 

 mashed potatoes, chopped cabbage, guano, or the dung 

 of the horse, pig, or sheep. But experience, according 

 to M. v. D. Borne and others, shows the necessity of 

 great caution, and the economical results of fattening 

 have not been satisfactory. Carp are often troubled by 

 the male frogs, which under the influence of sexual 

 excitement attach themselves firmly to tlie hesid of the 

 sluggish Carp, and with their forefeet press the eyes 

 of the fish so hard as to pi'oduce blindness. 



For all this the Carp is an easilj' fed and easily 

 managed domestic animal; but without expensive pre- 

 paration for table its culinary value is even less than 

 that of the Pike. In the south of Europe its roe is 

 made into caviare, consumed principally by the Jews, 

 who are , forbidden by law to eat genuine caviare, the 

 Sturgeon being destitute of ordinary scales. 



The age attained by the Carp is not yet ascer- 

 tained. Buffon mentioned Carp 150 years old as exist- 

 ing in the moats at Pontchai'train, and Lebel stated 

 that the ponds at Lausitz'' contained Carp 200 years I 

 of age. It is difficult, however, to test the truth of ' 



these old statements, and the same difficulty applies to 

 Block's account" of the capture in 1711, at Bischof- 

 hausen near Frankfurt-on-the-Oder, of a Carp 6 feet 

 long, 2'/5 feet deep, with scales as large as an 8- 

 groschen piece, and 70 lbs. in weight. In a state 

 of freedom, according to Heckel and Knek (1. c, p. 

 57), the Carp only attains the age of about 12 or 15 

 years. 



As we have mentioned above, many cultivators 

 of the Carp are unfortunate enough to have their 

 breed of fish spoilt liy crossing with the Crucian Carp. 



The liybrid produced by this cross-breeding has gene- 

 rally been known among modern ichthyologists by the 

 name of 



" Cuv., Val., Hist. Nat. Poiss., vol. XVI, p. 57. 



' See LACEPfeDE, Hist. Nat. Poiss., tome V. p. 510 nnd Bloch, Natiirg. DeutxM. Fish., part. I, p. 95. 



' Cited from Beokmanns Gesch. der Clmr., Th. I, p. 574. 



