SALMON. 
853 
Length of the body expressed in millimetres - 
Length of the head.. in % of the length of the body 
„ „ „ „ reduced (from the hind extremity of the intermnxillaries to the hind mar- 
gin of the preoperculum).. „ „ ,, „ „ „ ,, „ 
Breadth of the interorbital space „ „ ,, „ „ ,, „ „ 
Length of the snout „ „ „ ,, „ „ ,, „ 
„ „ „ maxillaries - „ „ „ „ „ „ „ „ 
„ „ ,1 lower jaw „ „ „ „ „ „ „ „ 
Longitudinal diameter of the eyes „ „ „ ,, „ ,, „ „ 
Vertical . . ,, n n n n n ,, ,, ,, n „ 
Length of the suboperculum „ „ „ „ „ „ „ „ 
Distance between the dorsal fin and the tip of the snout „ „ „ „ ,, „ „ „ 
Base of the dorsal fin „ „ „ „ „ „ „ 
Height ,, ,, » i, 11 H 11 11 n 11 11 11 
Length of the pectoral fins „ „ „ „ „ „ „ „ 
Preabdominal length „ „ ,, ,, „ „ ,, „ 
Distance between the ventral fins and the tip of the snout ,, „ „ „ „ „ „ „ 
Length of the ventral fins „ „ „ ,, „ „ „ „ 
Postabdominal length... „ „ „ „ „ „ „ „ 
Base of the anal fin.. „ „ „ „ „ „ „ „ 
Height ,, ,, ?J ,, ,, ,, ,, ,, ,, ,, ,, ,, 
Dorsal margin of the peduncle of the tail „ „ „ „ „ „ „ „ 
Ventral ,, ,, . . ■ • ^ >> 
Least depth of the tail ,, „ „ „ „ „ „ „ 
Length of the middle caudal rays „ „ „ „ „ ,, „ 
i? ;) longest ,, ,, ,, ,, ,, „ ,, ,, 
Breadth of the maxillaries in % of the length of the head reduced.. 
n 5 ? y> ii ii ii ii ii ii ii maxillaries 
Number of gill-rakers in the outer row on the first branchial arch of the right side. 
1 pff 
55 55 55 5 5 55 55 55 55 55 55 55 55 55 55 AC - LU 55 -- 
Number of scales in a longitudinal row = Vio of the length of the body just above the lateral line and in front of the dorsal fin 
55 55 5’ 55 55 55 55 55 55 55 55 55 55 55 5 5 55 55 55 55 55 5 5 abOVC the UUal fin 
Trout. 
True 
Salmon. 
Salmons. 
Charr. 
361 
391 
364 
333 
22.2 
20.8 
21.4 
21.5 
14.9 
13.5 
14.6 
14.4 
7.2 
6.9 
7.2 
6.9 
6.9 
6.7 
6.9 
6.6 
8.9 
7.2 
8.6 
8.5 
13.6 
11.7 
13.3 
13.4 
3.4 
3.2 
3.4 
3.3 
3.i 
2.9 
3.1 
3.o 
5.4 
5.2 
5.4 
4.9 
42.3 
41.3 
42.i 
43.7 
11.8 
11.5 
11.8 
10.3 
12.5 
11.0 
12.3 
11.9 
15.i 
14.6 
15.o 
14.9 
29.o 
29.7 
29.i 
28.9 
49.2 
49.i 
49.i 
49.2 
11.8 
10.8 
11.7 
11.6 
20.4 
20.6 
20.4 
20.9 
8.5 
7.9 
8.4 
8.4 
12.2 
9.6 
11.8 
10.5 
11.3 
12.i 
11.3 
12.o 
12.1 
13.3 
12.4 
13.o 
8.9 
7.4 
8.6 
7.2 
7.8 
6.o 
7.5 
6.9 
14.4 
14.5 
14.4 
15.i 
14.8 
13.4 
14.5 
12.4 
24.7 
25.i 
24.7 
21.o 
15 
18 
— 
23 
15 
18 
— 
24 
20 
18 
— 
30 
17 
15 
— 
26 
The first two columns of this table show 1) the 
differences between typical Trout and Salmon, 2) the 
developmental alterations of Salmons during the more 
advanced stages of growth, the latter partly because 
the Trout, as we have proved above, in most of their 
characters represent the earlier stages of growth, partly 
because the specimens measured were on an average 
shorter than the typical Salmon included in the table. 
The last two columns, on the other hand, show the 
relation of the Salmons to the Charr; and although the 
Charr measured were on an average shorter than the 
Salmons, still we see that in the great majority of 
cases the percentages of the former betoken a more 
advanced development, in the direction indicated by 
the ' changes of growth in the first columns of the 
table. Where the relation is the contrary, and cannot 
be explained by the difference of age, as in the case 
of the distance between the dorsal fin and the tip of 
the snout in proportion to the length of the body, or 
the breadth of the maxillaries in proportion to their 
length, another factor, the difference of sex, has as- 
serted itself. In the males the dorsal tin is, as a rule, 
situated further back, and the maxillaries are longer, 
than in the females; and here the Charr represents the 
male characters. 
The Salmon, like other fishes, is subject to va- 
rious malformations. These are especially prevalent 
and have received most attention at hatcheries", where 
the fry live under more or less unnatural conditions, 
and where there is better opportunity for observation 
than in nature. One of these deformities, that may 
often be seen, is the so-called pug-nose (reduction of 
° See, for example, Day, British and Irish Salmonidce, pi. XII. 
