1024 
SCANDINAVIAN FISHES. 
The Common Eel, with which most of our readers 
are, no doubt, familiar, attains a length of about 1 x / 2 m. 
and a weight of about 5, perhaps 6 kilo." Its ordinary 
length and weight, however, are respectively under 1 m. 
and 2 kilo. The snake-like body is so terete in front 
that the greatest breadth (thickness) is sometimes equal 
to the greatest depth, or even (when the branchial ca- 
vity is distended) greater than it; but the former is 
commonly no more than i / 5 or 3 * * / 4 of the latter, and 
at the termination of the abdominal cavity the body 
shows greater and greater lateral compression. The 
greatest depth, which occurs just in front of the dorsal 
tin, increases with age in the young, though even at a 
length of 4 1 / 2 dm. it sometimes measures, according to 
Kroyer, only about 57 a % thereof; but the rule is that 
it subsequently decreases during growth, falling in Eels 
measuring 4 — 7 dm. from 7 to 6 % of the length of 
length of the body increases from about 27 2 to 67 a dm., 
that of the head decreases in our specimens from 13 to 
11 % of the former 6 , or from about 41 to 36 % of the 
distance between the dorsal fin and the tip of the snout. 
But in this respect we find that older Eels — we can 
speak here only of females — and certain individuals 
which it has been proposed to treat as a separate spe- 
cies or variety ( latirostris ), revert to the juvenile cha- 
racters, or even exceed the limits of these, the length of 
the head sometimes measuring 15 % of that of the body 
or 46 % of the distance between the dorsal fin and the 
tip of the snout. The form of the head is also highly 
variable, in front more or less conical (acutir ostris) or 
broader and depressed, wedge-shaped ( latirostris ), and 
behind more or less tumid, depending partly on the 
greater or less distension of the branchial cavity, partly 
(behind the eyes) on the varying development of the 
Fig. 275. Three varieties of Anguilla vulgaris. A, Anguilla latirostris; B, Angu. merliorostris ; C, Angu. acutirostris. 
After Blanchere. 
the body. Still large Eels grow to the thickness of a 
man’s arm. The males seem always to remain smaller 
than the females, for up to the present large specimens 
have been found in every instance to be of the latter sex. 
The head passes so gradually into the rest of the 
body that the limit between them is externally almost 
indistinguishable, being indicated only by the position 
of the small gill-openings, just in front of and partly 
below the pectoral fins. The size of the head is ex- 
tremely variable. After the larval stage its relative 
length (to the middle of the anterior margin of the 
gill-opening) shows the usual diminution. While the 
masticatory muscles. The usual proportions of the se- 
veral parts of the head are such that the length of the 
snout is 20 % or somewhat less (17 %), the longitudinal 
diameter of the eyes 10 % or somewhat less (in young 
Eels at least 13 in old sometimes 7 %), and the 
postorbital length about 70 % (varying in individual 
cases between 68 and 75 % c ), of the length of the head. 
The eyes, which are covered with a thin skin that still 
further enhances the snake-like appearance of the Eel, 
are sometimes set vertically, sometimes rather upturned. 
Partly in consequence of this variation in the position 
of the eyes, partly following the alterations of growth, 
a According to the reports made to the Swedish Fisheries Commission of 1881 — 83, the Eel- — which occurs in every province of 
Sweden — attains in Wermland, Westmanland, and Westernorrland a length of 5 Sw. ft. (148 cm.) and in the last-mentioned province a weight 
of 15 Sw. lbs. (S'/g kilo.). According to Desmarest the Eel attains a length of at least 17 dm. and a circumference of at least 3 x / 2 dm. 
6 According to Kroyer this percentage sometimes falls to 10. 
c According to Kroyer sometimes nearly 77 %. 
