Cyprinidae 3 1 



quite abundant in certain localities. These hybrids are in every 

 way intermediate between the parent species. 



The hybrid Bream and Eoacli {Abrainis })rama x litiiilit:^ 

 rutilm) has the form of a deep Eoach ; the anal fin is rather long, 

 and lias 15 to 19 branched rays. A very fine example of this 

 hybrid (51), weighing 3 lbs. 10 ozs., is exhibited ; it is from a lake 

 at Tortworth, Gloucestershire, and was presented in 1914 by the 

 Earl of Ducie, F.E.S. 



The hybrid Bream and Eudd {Abramis bramn x ScardinniH 

 erythrophthahnus) differs from the Bream and Eoach hybrid in 

 the same characters that the Eudd differs from the Eoach — body 

 usually a little deeper, mouth more oblique, dorsal fin a little 

 farther back, etc. This fish is well known to the Lough Erne 

 fishermen, who call it " White Eoach." One of a series from 

 Lough Erne presented by the late Major H. Trevelyan is exhibited 

 (52) ; the largest of these weighed 2 lbs. 



53- Bleak, Alburnus lucidus. — This pretty and lively little 

 fish shows more resemblance to the Dace than to the Breams in 

 its elongate form and bright silvery coloration ; its relationship is 

 really with the Breams, as is shown by the rather long anal fin 

 and the sharp edge of the abdomen in front of it. k silvery 

 powder extracted from the scales of the Bleak is used in France 

 in the manufacture of artificial pearls. The Bleak inhabits 

 Europe north of the Pyrenees and Alps ; in Britain it is absent 

 from Scotland, the Lake District, and the counties bordering the 

 Channel ; it does not occur in Ireland. It grows to a length of 

 8 inches. The specimen exhibited, from Weybridge, was presented 

 by F. Page, Esq., in 1915. 



54. 55- Bleak Hybrids. — The Bleak is known to form hybrids 

 with the Dace, Chub, Eoach, Eudd and White Bream. The 

 commonest of these is the hybrid Bleak and Chub {Alburnus 

 lucidus X Leuc'iscus cephalus), which is represented in the 

 Museum by specimens from the Mole, the Thames, and from a 

 reservoir near Oundle ; a model of one from the first-named 

 locality is shown (54). This hybrid combines the physiognomy of 

 both parents ; the anal fin has 10 to 13 branched rays. The 

 other Bleak hybrids are rare ; of the two examples known of the 

 Bleak and Eoach hybrid {Alburnus lucidus x Butilus rutilus) 

 one was taken in the Eiver Nen in 1889. A model of this is 

 exhibited (55) ; it has a deeper body than the hybrid Bleak and 

 Chub. 



