795 



took specimens 2*1 — 25 mm. liin<;' at tlir lieuiniiiiii,' nf 

 October. Fislienueu in general believe tli.'it the l>le;il< 

 spawns three times a year at short intervals; and from 

 Lorama (Scania) we are told by AsTUOii" that at Whit- 

 suntide three slujals of Bleak generally enter the stream 

 from the Sound, and spawn one after the other at 

 intervals of about a week. But the true explanation 

 of this fact is tliat the difference in the spawning-season 

 depends on the different ages of the fish, for the Bleak 

 that spawn first are always larger tiiaii tliosc wliidi 

 spawn latei'. Bleak are taken in numbers only iluring 

 the sjiawning-season. The tackle most employed con- 

 sists of a small and fine-meshed seine, constructed 

 especially lor this purpose, and called lojnot or lor/skote 

 (I'jlcak-seine or Bleak-net), or a large circle-net (Sw. 

 (iriji). which is cast over the shoal while spawning. 

 In suuuner the Bleak may also be taken in small- 

 nieshed nets and in traps; but the catch is seldom 

 large. After the s[)awning-seasou it takes a bait freely, 

 a fly being an especially tempting morsel. 



As the Bleak is small, and is only seldom taken 

 in large nnml)ers, it cannot possess any great impor- 

 tance as an article of food. It is generally eaten fresh, 

 its flavour, when fried, being not unlike that of the 

 Baltic Herring. When salted or dried it entirely loses 

 its flavour. It is most useful to the fisherman as bait, 

 for which purpose it is excellent, though not as live 

 bait, its tenacity of life being small. It is eagerly 

 sought after by terns and gulls, which generally flock 

 to the places where Bleak are to be found, and it is 

 one of the most important foods of our best and most 

 valuable predatory fishes. When pursued by them, 

 it may often be seen leaping in companies out of the 

 water. In an aquarium it is a lively, j)layful, and 

 amusing jiet. 



In France the Bleak has been much in request 

 since the year 1680", when a manufacturer of beads, 

 Jacquix by name, discovered a method of a])plying 



the silver}- pigment from its scales to practical use. 

 With tliis sul)stance, the so-called essence d'orient, he 

 coloured the inner surface of hollow glass beads, which 

 were then filled with wax, an excellent imitation of 

 the genuine pearl being thus produced. Millions of 

 Bleak were used in this way, and great (jtiantities of 

 Bleak scales imported to Paris, the chief seat of this 

 manufacture. It is estimated, according to Bl.vnchard, 

 that about 4,000 Bleak yield half a kilogramme of 

 scales, and that the proportion of the C(jlouririg matter 

 to the total weight of the scales is as 1 to 7. 



(,'entral Europe is inhabited by three forms whose 

 signification was difficult to explain, until Siebold's 

 suggestion that they \vere hybrids between the Bleak 

 and other species, was generally accepted. One of 

 them is the form described by Holandre' in 18.36 

 from the Moselle under the name of Leticiscns dola- 

 bratus, and by GCntuer from the Neckar, first'' under 

 the same name, subsequently" under that of AJburnus 

 dohuloides. This variety was elucidated by Siebold-^ 

 as a hybrid between the Chub and the Bleak, and be- 

 longs to the basins of the Maas, Rhine and Danube. 

 It is usually as small as a Bleak and also of the same 

 appearance, though with less ascending mouth, less 

 prominent lower ja\v, and shorter anal fin with straight 

 or rounded (convex) margin. But it sometimes attains 

 a length of at least 31 cm., and is then more like a 

 Chub, with the scales pigmented at the hind margin 

 with black. The pharyngeal teeth resemble those of 

 the Bleak. 



Another similar form has been described by Jac- 

 kel' from Bavaria under the name of Alhurnus Bosen- 

 Jtaiteri, and by Benecke'' from Deutsch-Eylau (Prussia) 

 under that of Scardiniopsis alhurniformis. Both these 

 authors interpret it as a cross between the Rudd and 

 the Bleak. Its body, according to Benecke, is deeper' 

 than that of the Bleak, its scales are coarser and gen- 

 erally fewer (45 — 47 in the lateral line), the anal fin 



" Ndgra iakttaijeUer riirande de vertebre.rade djur, som /urekomma i trakten af Lomjiia, disp. Lund 1859, p. 27. 



* See Blanchard, 1. c. In Reacmup. — Hist, de I'Acad. Roy. d. Sciences, An. 1716, p. 229 — the discovery is said to have been 

 made in 1656. 



' F'luiia dn Dt'partement de la Moselle, p. 248. 



•' .lahresb. Ver. Vat. Xaturk. Wurtemb., .Jahrg. IX (1853), p. 314. 



Xm (1857), p. 51, laf. II. 

 ■' Siisswasserf. Mitteleur.. p. 164. 

 ^ Zoo!. Garten 1866, p. 20. 



* Zool. Anzeiger 1884, p. 228. 



' 22 °i of the length of the body to the end of the lower caudal lobe corresponds to 24 % of the length to the tip of the middle 

 caudal rays, and is a measurement by uo means uncommon, at least in gravid females of the common Bleak. 



