ae 
of the Fishery Board for Scotland. 65 
Gadus merlangus, Linn. The Whiting. Pl. ui. 4., figs, 6-8, 30 and 31. 
The earstones of numerous whitings have been examined, and all, 
except those of very small specimens, agree in the peculiar form by which 
they may be distinguished from other species of Gadus. They are 
elongated and narrow. The lower margin is tolerably even and slightly 
convex. The anterior end is obliquely truncated, and with the edge 
usually crenulate. The upper margin, for about two-thirds of its length, 
from the anterior extremity, is nearly straight and parallel with the lower 
edge, then it gradually converges towards the lower margin, so that the 
posterior end is narrow and tapering and has a sharp-pointed termination. 
The earstones are somewhat concave outwardly, and slightly convex and 
nearly smooth on the inside. The lower edge is tolerably thick, while 
the upper, especially where it begins to taper towards the posterior end, 
is compressed and thin. 
Photographs are given of the earstones of five whitings which measured 
respectively 14 inches, 123 inches, 112 inches, 11? inches, and 9 inches in 
extreme length, and the size of their earstones given in the same order is as 
follows :—20mm. long by 5mm. in greatest width (fig. 30), 16mm. by 
about 45mm. (fig. 8), 16°5mm. by nearly 5mm. (fig. 7), 15mm. by about 
4-7mm. (fig. 6), and 125mm. by about 4mm, (fig. 31). The earstones of 
two young whitings, about 68mm. (2? inches) in length, but which are 
not represented among those photographed, measured 3°5mm. by about 
1‘5mm., which is fully twice the length of those of a lumpsucker 154 
inches long. 
By comparing the length of the earstones of a number of whiting of 
average size with the length of the fish they were taken from I found 
that, though the proportion varied to some extent, the length of the 
earstones approximated to about one-eighteenth part of the extreme 
length of the fish. 
The proportion between the length of the earstones and of the fish 
they belong to varies considerably in the different kinds of fish. An 
examination of numerous examples of fish belonging to various species 
seems also to indicate that where the earstones are massive in structure, 
as in some of the Gadoids, they are shorter in proportion to the length of 
the fish than those that are thin and narrow. This may tend to explain 
why the earstones of the whiting are generally proportionally more 
elongated than those of the haddock or codfish. 
Gadus virens, Linn. The Saithe or Coal-fish. Pl. i. a., figs, 14-16. 
The earstones of large coal-fish are very massive in structure. Fig. 14 
represents those of a fish of average size, but I am unable to state the 
exact length of the fish, though it could not be much under 36 inches. 
These earstones measure about 24mm. long by about 8mm. in greatest 
width. The upper and lower margins are tolerably straight and nearly 
parallel, and they are slightly ecrenulated along the edges. The front end 
is somewhat obliquely truncated, but at the posterior end the upper and 
lower margins converge so that they meet and terminate in a blunt point. 
They are also slightly twisted, and have the outer side incurved and 
slightly rugose, while the inner side is convex and nearly smooth. 
Figs. 15 and 16 represent the earstones of two saithe about 15 inches 
long; they are narrow and elongated, and small when compared with 
those of the whiting. These earstones measure from 1lmm. to about 
115mm. in length, which is equal to about the one thirty-third part of 
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