774 
SCANDINAVIAN FISHES. 
vol. Ill, p. 435; Nilss., Skand Fn., Fisk., p. 316; Sundev. 
(Cyprians'), Stockh. L. Hash. Sallsk. Handl., H. 6 (1855), 
pp. 81 et 174; Vet.-Akad. Handl. 1855, p. 13; Hckl, Kn. 
' ( Leuciscus ), Siisswasserf. Oest.r. Mon., p. 169 (+ L. Pau- 
singeri , p. 172); Dye., Cypr. Liv., p. 36; Sieb., Siisswasserf. 
Mitteleur., p. 184; Mgrn, Finl. Fiskfn ., p. 46; Widegr. 
(Cyprinus), Landtbr. Akad. Tidskr. 1863, pp. 201, 202, 207; 
Lindstr. ( Leuciscus ), Gotl. Fisk., Gotl. L. Hush. Arsber. 
1866, p. 17 (sep.); Blanch., Poiss. d. eaux douces Fr., p. 
382 (+ Leuc. pallens, p. 386); Gthr, Cat. Brit. Mus ., 
Fish., vol. VII, p. 212; Coll., Forh. Yid. Selsk. Christ. 
1874, Tillsegsh., p. 180; ibid. 1879, No. 1, p. 96; Olss., 
Ofvers. Vet.-Akad. Forh. 1876, No. 3, p. 130; 1882, No, 
10, p. 48; Malm, Gbgs, Boh. Fn., p. 557; Bncke, Fisch., 
Fischer ., Fischz., O., W. Preuss., p. 136; Mor., Hist. Nat. 
Poiss. Fr., tom. Ill, p. 413; Fatio, Fn. Vert. Suisse , vol. 
IV, p. 479; Mela, Vert. Fenn., p. 323, tab. X; Grimm, 
Fish., Hunt. Russ. Wat., p. 14; Day, Fish. Gt. Brit., Irel., 
vol. II. p. 175, tab. CXXXII, fig. 2; Mob., Hcke, Fisch. 
Osts., p. Ill; Reut., Sundm., Finl. Fisk., tab. XI; Lillj., 
Sv., Norg. Fn., Fisk., vol. Ill, p. 189. 
Leuciscus Heckelii, Nordm., Voy. Russ. Merid. (Demid.), tom. 
Ill, p. 491, tab. 23, fig. 1; vide Grimm, 1. c. 
The Roach does not grow to any great size. Most 
of the specimens caught during the spawning-season 
are 15 — 20 cm. long, but many attain a length of 3 
dm. The largest specimen in the Royal Museum is 
from Lake Wetter, and measured 3 1 /, dm. Nilsson 
once saw a Roach 371 mm. long". At a length of 
230 — 248 dm., according to Fatio, the Roach weighs 
120 — 160 grammes 6 . 
The body is rather thick, but compressed, and 
generally thinner than that of the Ide. The greatest 
depth varies between about 24 and 28 1 / 2 % of the length 
of the body, the percentage being highest in old spe- 
cimens and the females; while the greatest thickness 
usually measures only 36 — 41 % of this depth, though 
in gravid females it may rise to 54 % of the same. 
The back ascends without forming any abrupt curve 
from the occiput to the beginning of the dorsal fin, 
from which point it slopes almost in a straight line to 
the caudal fin. Throughout the greater part of its length 
it is convex, but a little in front of the dorsal fin more 
or less distinctly compressed or even carinated. In front 
the downward curve of the ventral margin is similar 
to the upward curve of the dorsal; but between the 
ventral fins and the anal aperture the belly is almost 
straight and slightly but distinctly carinated, and at the 
beginning of the anal fin it rises at an obtuse angle. 
The head resembles in form that of the Ide, save 
that here the forehead is narrower 0 and straighter, and 
the snout more pointed, with a similar faint depression 
in front of the nostrils. The length of the head is 
also somewhat less, varying between about 2 1 x / 2 and 
20 % of that of the body. The mouth is still smaller 
than in the Ide, the length of the upper jaw from the 
tip of the snout being always less than that of the 
latter and varying with age J between about 27 and 24 
or 25 % of the length of the head. The length of the 
lower jaw varies simultaneously between about 36 and 
32 % of that of the head, and is always less than (about 
95 — 84 % of) that of the suboperculum along the suture 
at the lower margin of the operculum. The longitu- 
dinal diameter of the eyes varies in the same speci- 
mens between about 27 and 18 % of the length of the 
head, or between about 75 and 48 % of the breadth of 
the interorbital space. The postorbital part of the head 
always measures somewhat less than half the entire 
length of the same, unless the rim of the branchiostegal 
membrane be taken into account, in which case it 
slightly exceeds half the said length. The position of 
the eyes is also such that the lower margin of the pu- 
pil touches the line from the middle of the caudal fin 
to the margin of the upper jaw. The nostrils resemble 
those of the Ide. The gill-openings are separated be- 
low, here as in the preceding forms, by the isthmus, 
which is rather narrow, and to which the branchiostegal 
membranes are united. The pseudobranchiae are free 
and comparatively large in young Roach, in older spe- 
cimens less distinct. The gill-rakers are short and 
scattered, numbering 10 — 14 in the outer row on the 
first branchial arch, 10 on the outer margin of the 
pharyngeal bones. In contradistinction to the three 
preceding species, the Roach (fig. 192) has only one 
row of teeth on each of the pharyngeals, generally 6 
on the left and 5 on the right, though these numbers 
may vary, being sometimes only 5 on each side, some- 
times 6. The first two teeth, here as in the preceding- 
forms, are almost straight, blunt, conical, and without 
a M6bius and Heincke give 5 dm. as the maximum length of the Roach. 
b According to Isaak Walton the Roach may attain a weight of 2 lbs. (907 grammes); and in ‘The Field’ (2 Nov., 1881) we read 
of a Roach weighing 3 lbs. 1 2 1 2 oz. (949 grammes), taken by Mr. Stead in Bedfordshire. 
c The breadth of the interorbital space is less than 38 % (35 — 37’8 %) of the length of the head, or than 2 / 3 (52 — 64 %) of the 
length of the base of the dorsal fin. 
In our specimens, which are between 100 and 330 mm. long. 
