BLEAK. 
795 
took specimens 20 — 25 mm. long at the beginning of 
October. Fishermen in general believe that the Bleak 
spawns three times a year at short intervals; and from 
o 
Lomma (Scania) we are told by Astrom" that at Whit- 
suntide three shoals 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 that the difference in the spawning-season 
depends on the different ages of the fish, for the Bleak 
that spawn first are always larger than those which 
spawn later. Bleak are taken in numbers only during 
the spawning-season. The tackle most employed con- 
sists of a small and fine-meshed seine, constructed 
especially for this purpose, and called lojnot or log skate 
(Bleak-seine or Bleak-net), or a large circle-net (Sw. 
grip), which is cast over the shoal while spawning. 
In summer the Bleak may also be taken in small- 
meshed nets and in traps; but the catch is seldom 
large. After the spawning-season it takes a bait freely, 
a fly being an especially tempting morsel. 
As the Bleak is small, and is only seldom taken 
in large numbers, 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, playful, and 
amusing pet. 
In France the Bleak has been much in request 
since the year 1680 * * * * * 6 , when a manufacturer of beads, 
J ac quin by name, discovered a method of applying 
the silvery pigment from its scales to practical use. 
With this substance, 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 quantities of 
Bleak scales imported to Paris, the chief seat of this 
manufacture. It is estimated, according to Blanchard, 
that about 4,000 Bleak yield half a kilogramme of 
scales, and that the proportion of the colouring matter 
to the total weight of the scales is as 1 to 7. 
Central Europe is inhabited by three forms whose 
signification was difficult to explain, until Siebold’s 
suggestion that they were hybrids between the Bleak 
and other species, was generally accepted. One of 
them is the form described by Holandre'* in 1836 
from the Moselle under the name of Leuciscus dola- 
bratus, and by Gunther from the Neckar, first d under 
the same name, subsequently 6 under that of Alburnus 
dobidoides. This variety ivas elucidated by Siebold 7 
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 jaw, 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- 
kei/ / from Bavaria under the name of Alburnus Bosen- 
haueri , and by Benecke 7 ' from Deutsch-Eylau (Prussia) 
under that of Scardiniopsis alburniformis. 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 
* Nagva iakttagelser rorcmde de vertebrerade djur , som forekomma i trakten af Lomma, disp. Lund 1859, p. 27. 
b See Blanchard, 1. e. In Reaumur — Hist, de l’Acad. Roy. d. Sciences, An. 1716, p. 229 — the discovery is said to have been 
made in 1656. 
c Fauna du Departement de la Moselle, p. 248. 
d Jahresb. Ver. Vat. Naturk. Wiirtemb., Jahrg. IX (1853), p. 314. 
6 „ „ „ „ „ „ XIII (1857), p. 51, taf. II. 
f Siissivasserf. Mitteleur., p. 164. 
g Zooi. Garten 1866, p. 20. 
h Zool. Anzeiger 1884, p. 228. 
1 22 % 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 no means uncommon, at least in gravid females of the common Bleak. 
