— 123 — 
Table 2. 
Coalfish 45.3, 65th cross row Cod 34.0 cm. 101st cross row 
No. 4 So Bo : x Go Bo 
No a B NE 8 | No a B = 8 
| if 
1 ae 146 a 33 1 93 162 70 67 
2 et 145 se 33 2 89 155 67 68 
3 pa 140 1 35 5 87 149 69 70 
4 N 145 Be 37 7 86 145 71 70 
5 BE 148 RE 9 7B | 18 67 67 
6 ER 147 ee 35 | 10 74 | 130 69 69 
7 AO ae 35 11 78 | 136 2 | 6 
8 an TAT iene: al 55 12 76 | 136 1 | @ 
9 Se 147 Re ABS 3 7 | ws 71 72 
110 Re 18) Sr ee 14 69 122 72 71 
ees RE ee | ee 31 15 || 1) | WB |) a0 
12 ” EE ee 32 | 16 66 | 123 10 | 6 
Average — ee |) CHS | Average — 70:25 | 69:0 
| | 
m = en | vee | BAG || m= + | 2.69% | 2.39 lo 
| Il 
now remains to be considered. Owing to lack of suitable material, it has not hitherto 
been possible to arrive at a final determination on this point. It may however, safely 
be asserted that the variations which may occur are only slight, and appear, moreover, 
to be partly of a regular nature. One of the causes of dissimilarity between the size 
of the scale and the length of the fish which we find in the herrmg does not arise in the 
case of the cod and coalfish, viz, the relative size of the scale-covered part of the body. 
This factor, which in the case of the herring increases until maturity is reached, exhibits 
no regular alteration with age in the cod and coalfish, save in the case of quite small spe- 
cimens. On the other hand, the irregularity in the size of the scales renders the rela- 
tion between the growth of the scale and that of the fish less distinct, when judging merely 
by comparison of the size of several individuals and the size of certain of their scales. 
The best method would be to keep fish in captivity, measuring their scales at different 
ages — a method which is scarcely feasible as regards the herring, but which might well, 
and doubtless will, be employed in the case of the cod family. Table 3 will serve to 
give an idea of the relation between the size of the scale and the length of the body for 
coalfish, Table 4 showing corresponding figures for cod. L = total length, T = length 
exclusive of head and tail fin, E = size of scales from the vicinity of the lateral line below 
the forepart of the second dorsal fin, H = size of scales from the vicinity of the lateral 
line below the forepart of third dorsal fin. 
“The figures given in the above tables as for accuracy of the agreement between 
the size of the scale and length of the fish (5.5—8.3 %) correspond to those found by 
LEA in the case of the herrmg, viz: 6—7 %.” 
These methodical investigations suffice to show that the scales of the cod may be 
used as a means to exact study of the growth of the fish; there remains the important 
