LEUCISCTJ8 PIGUS. 153 



becomes bluish-red as it extends forward. The opercular region and all the 

 scales shine with an oixalescent splendour, which is not equalled by any other 

 European Cyprinoid. The upper part of the dorsal fin becomes reddish, the 

 pectorals yellowish, and the pale red of the ventral and anal fins changes into 

 deep orang-e, while the caudal becomes a yellowish -red. These colours increase 

 in brilliance to the end of April or beginning of May, the back becoming darker, 

 the snout bluish-red, while the cheeks and operculum have a silver ground 

 with a play of colour which changes to rose-red, violet, azure-blue, green, 

 or yellow ; and all the fins become bright red. After spawning, the colours 

 fade, and the cicatrices left where the pearly gfowths fell off gradually 

 disappear. 



There are twenty-seven vertebra? in the dorsal region, and nineteen in 

 the tail. 



The Leachcns roseas of Bonaparte is probably a variety of L. pigus. 

 It is known only from the Lakes of Piedmont, and is so rare that Canestrini 

 has never seen a specimen. The differences of proportions are all small 

 and unimportant. The rose colour is its most distinctive attribute ; and 

 Fatio suggests that it is a local pale-coloured variety of L. pigns, comparable 

 to the pale-coloured varieties of the Roach. 



The LeitciscKS pigus is captured by the Italian fishermen chiefly in the 

 early morning. During the breeding season it is taken in great numbers with 

 the net. As soon as the fishes are seen on the surface the net is extended 

 round them, and they are sometimes driven into shallow water. It is a vora- 

 cious fish, to which nothing comes amiss which can be swallowed, though 

 its foul feeding does not affect its quality as food. When taken in great 

 quantities the Italians salt and dry it in the sun for winter use. 



Leuciscus friesii (Nordmann). 



D. 11—12, A. 1:2—14-, V. 10—11, P. 20, C. 19. 

 Scales : lat. line CI — (37, transverse 11/S. 



This species is found in the mountain lakes of Bavaria, like the Chiem See ; 

 in the After See and Mond See in Upper Austria, and is known from the Lake 

 of Derkos, near Constantinople, and is met with in the Sea of Azov and the 

 less salt parts of the Black Sea, and in the central and southern parts of 

 the Caspian, where it ascends the rivers Koora and Terek. 



The species is well defined by its elongated, nearly cylindrical form, and 

 small scales, though the proportions vary with the locality (Fig 79). The 



