782 
SCANDINAVIAN FISHES. 
more southern countries earlier, sometimes even in April. 
The males and females then join company and gather 
in shallow, weedy inlets, where the spawning takes 
place, accompanied by a babbling or smacking noise. 
This sound is produced by the fish putting their snouts 
to the surface, opening the mouth, and emitting an 
air-bubble, which floats on the water and bursts. The 
roe is deposited on the weeds, and is hatched in 8 — 10 
days, the length of time required depending on the 
weather. In a female weighing 293 grammes Bloch 
estimated the number of the eggs at 91,720. 
The Rudd is used as food only by the poor. The 
flesh is flabby, bony, and always more or less tainted 
with mud. Furthermore, as the fish is hardly ever 
found, even during the spawning-season, in large shoals, 
it is only seldom that the fisherman pays any special 
attention to it. Traps ( ryssjor , see p. 33, fig. 7) are 
set at the spawning-place, in which case care should 
be taken to lay them close to the bottom. Wicker- 
baskets ( mjardar , see p. 32, fig. 6) may also be em- 
ployed at the spawning-place, but are less useful. In 
the trammel-net the Rudd is taken all the summer on 
warm and tine days and at places thickly overgrown 
with weeds. The trammel should be shot among the 
weeds, for if it be set outside them, the Rudd refuses 
to be driven into the meshes. By angling it may also 
be caught throughout the summer, for it bites eagerly 
at a worm. It is almost always taken in company 
with other fishes. 
The Rudd’s fondness for joining, as an interloper, 
in the spawning of other fishes has produced several 
hybrids, one of which, Jacket s“ Scardiniopsis anceps , 
is a cross between this species and the preceding one. 
In this form the position of the dorsal fin is the same 
as in the Roach; but the size of the scales and the 
pectination of the pharyngeal teeth remind us of the 
the Rudd. The dorsal fin contains 10 branched rays, 
the anal 11 or 12. The number and distribution of 
the pharyngeal teeth vary, being, according to Jacket., 
5 — 5; 6 — 5, 1; 1, 5 — 5; or 1, 5 — 5, 2. This hybrid 
occurs in Bavaria, but has not yet been found in 
Sweden. Another hybrid form, a cross between the 
Rudd and the Bleak, is also unknown in Sweden; 
but a third, the result of cross-breeding between the 
Rudd and the White Bream, has been met with in 
this country, and a brief notice of this variety will be 
found below. 
(Ekstrom, Smitt.) 
Genus ASPIUS'. 
Scales middle-sized. Lateral line complete. Lower jaw distinctly prominent , with the point fitting into an in- 
dentation in the tip of the snout. Caudal lobes pointed. Length of the base of the anal fin more than 19 % of 
the distance between this fin and the tip of the snout. Beginning of the do'rsal fin situated in front of the 
middle of the body, and the distance between it and the tip of the snout less than 86 % of that between the 
anal fin and the same point. 
Thus defined, the genus contains only one spe- 
cies 0 , and is ranged by its flatly convex belly (only 
slightly carinated between the ventral and anal fins) 
beside the most typical Leuciscines, but owing to 
the comparatively great length of the anal fin forms 
a distinct link between the Leuciscines and the Abra- 
midines. The character by which Gunther distin- 
guished this genus from Alburnus, the short and 
scattered gill-rakers, as well as the wide gape, is an 
expression of its more predatory nature, a point in 
which this genus is unequalled by any of our other 
Cyprinoids- 
a Die Fische Bayerns , Abb. Zool. Miner. Ver. Regensburg, 9:tes Heft (1864), p. 64. 
6 Agassiz, Mem. Soc. Sc. Nat. Neucli., torn. I (1836), p. 38. 
c The Syrian Aspius vorax (Heckel, Russegg. Reise, Th. II, p. 1081, tab. X, fig. 3) has small scales and a short anal fin. The 
Chinese Aspius spilurus (Gunth., 4$ at. Brit. Mus., Fish., vol. VII, p. 311) has large scales and an elongated body, more closely resembling 
Alburnus. Kessler has described an Aspius erythrostomus from the Caspian and the Sea of Aral, and Jacowlev an Aspius hybridus from 
the month of the Volga; but these forms are otherwise unknown to us. 
