900 
SCANDINAVIAN FISHES. 
I 
Like the Vendace forms the muksun has long and dense 
gill-rakers; but the polcur, like the tschir, short and 
scattered ones. Furthermore the muksun has a compa- 
ratively shallow snout, the polcur a comparatively deep 
snout. The two forms as well as the typical Gwyniad 
live together in the Siberian rivers and the Arctic Ocean 
off their mouths; and the difference between them coin- 
cides in an eminent degree with the distinction drawn 
bv the fishermen in several Swedish lakes between the 
different kinds of Gwyniad in their catch. The muksun 
type they call blasik or gronsik (in Norrland asp, when 
large, or sikloja, when small); while the polcur type 
bears the names of sik, fetsik, storsik, hvitsik or botten- 
sik. The typical ndbbsik (Houting), with its conically 
prolongated snout, also belongs in fact to the polcur 
group. The shape of the snout has probably been em- 
ployed time out of mind by the Swedish fishing popu- 
lation as a character for separate varieties of Gwyniad ; 
but in 1831 Laestadius directed attention to the gill- 
rakers of the asp as a distinction from the sik a . That 
Widegren had also observed the last-mentioned cha- 
racter, appears from the drawings which he left at his 
death in 1878, and which we have been enabled here 
to reproduce (fig. 222, B — F, above, p. 891). 
These two groups of the true Scandinavian Gwyn- 
iads we distinguished in 1879 by the names of Core- 
gonus Wartmanni and Cor. lavaretus b ; and they are 
sometimes well marked even where they occur in the 
same lake (figs. 224 and 225). As an example we may 
adduce the Royal Museum collections from Lake Stor 
(Storsjon) in Jemtland. Seven bldsikar and six fetsikar 
show the following constant differences: 
Blasilcar. 
Fetsikar. 
Number of gill-rakers 
on the first branchial arch of 
each side 
34—45 
20—24 
Depth of the snout in % of the length of the head 
8 . 6 — 9.s 
11.1—12.3 
7? 77 77 7? 7? 77 
, „ „ „ „ „ reduced. 
11.4—13.2 
14.8 — 16.7 
77 77 7? 77 77 77 
, ,, breadth of the snout 
50.o — 62.5 
66.6—87.5 
7? 77 77 77 77 7? 
, „ length of the maxillaries ... 
27.3 — 35.7 
40. o — 46.2 
Length of the lower jaw in 
% of the length of the head 
4- 
T 
o 
40.9 e — 39.3 
„ „ „ „ „ „ 
,, „ „ „ „ „ „ reduced 
62.9 — 59. b d 
59.3 — 51.5 
„ „ „ maxillaries,, 
,, „ „ „ „ ,, lower jaw.. 
60.o — 66.7 
68 . 4 / — 73.o 
But on examining the Fetsik fry of this lake, we 
find that, even at a length of 70 — 80 mm., only the 
first three characters hold good. Thus at the outset 
of their development the two forms stand nearer to 
each other, even after the external shape of the body 
has assumed the character of the group. As is more 
distinctly shown by our figures, the bldsikar of this 
lake belong to the group characterized in Gunther * 5 6 ' 
by “snout vertically truncated,” the fetsikar, on the 
other hand, belonging to the group 7 * in which “the 
snout is obliquely truncated, with the nose protruding”. 
The same difference appears, however, between true 
bldsikar as well, for example in Lake Ring, where, to 
the best of our knowledge, only bldsikar are found 1 . 
It is still more difficult to maintain the distinction 
between the two groups where they occur together in 
the great Swedish lakes or in the sea. The Royal 
Museum collection of Gwyniads from Lake Wetter 
shows the most varying form of snout 7 , exemplifying 
almost all conceivable transition forms between shallow- 
snouted Gwyniads (which we have called tapinorlvynchi k ) 
— not represented, however, by fully typical speci- 
a “The Asp occurs in all the large lakes, up to Kilpisjarvi in Tornea Lappmark. Spawns in autumn, in the rivers in October. Is 
exactly like the Sik, but differs in the gills, whose spines in the Asp are long and fine.” L. L. L^stapius, MS in the Royal Museum. 
6 See the Swedish Special Catalogue at the Fisheries Exhibition in Berlin 1880. Besides the Gwyniads included in this catalogue, my 
tables of measurements (published in 1886 in Vet.-Akad. Handl.) were accessible in manuscript, and in the course of a public discussion I 
cited the results of these tables, results which render the specific determination within the lavaretus group so untrustworthy that we have 
rather to deal with local varieties (See Giglioli, Annali dell’industria e del commercio 1880 (Roma 1881), num. 29, p. 38). 
Subsequently NOsslin (1882), Klunzinger (1884), and Fatio (1885 — 90) have arrived at the same conclusion, with respect to the 
connexion between the characters derived from the appearance of the gill-rakers and those drawn from the form of the snout, as I maintained 
on the said occasion and published in 1882 in Ofvers. Vet.-Akad. Fork. But they adhere to the older opinion according to which several 
species may be determined with certainty, by means of these characters, within the lavaretus group. 
c 43‘5 in a single specimen. 
d 58'8 in a single specimen. 
e 44'4 in a single specimen. 
f 62'5 in the youngest specimen. 
g Cat. Brit. Mus., Fish., vol. VI, p. 187. 
h 1. c., p. 178. 
1 Cf. for example Smitt, Riksrn. Salmon., tail. Y, figg. 78- — 81, representing four bldsikar ( Coregonus Nilssonii ) caught at the same time. 
■> See Smitt, 1. c., tafl. IV, figg. 69 — 71 and tail. V, figg. 73 — 75. 
k From ran eivog, loiv, and Qiyyog, snout. 
