of the Fishery Board for Scotland. 138 
Otoliths. —Generally, the otolith of minutus was heavier, more massive 
than that of duscws, in fish of the same length. The bossing or marking 
on the concave surface of the earstone is more distinct in /uscus; it tends 
to become smoothed down in minutus. Two minutus of one length 
had very different otoliths; in one they were much more massive than 
in the other fish. 
The otolith of esmarkii shows a tendency to transverse ridging in place 
of, or in addition to, bossing on the concave surface. 
The clavicle, §c.—Slight differences are to be seen in the clavicle, post 
clavicle, and premawxilla between minutus and luscus. Thus, in the 
clavicle the ridge dividing the outer surface of the boue is broader and 
more prominent in Jwscuws than in minutus. The post clavicle of minutus 
has a curved expanded superior end; in duscus the head of the bone is 
expanded and bent a little off the straight. 
In the premaxilla the only noticeable difference was in the rather 
longer and narrower shape of the plate expansion on the distal part of the 
bone in minutus. ; 
Teeth. 
The teeth are small in Juscus and minutus and minute in esmarkit. 
A Discussion of the Species. 
Gadus luscus and G. minutus. 
Only a very brief notice of the literature is necessary. Yarrell gives 
characteristic figures of Juscws and minutus. The specific characters are 
treated only briefly. He says with regard to Jwscus that it has the 
power of inflating a membrane which covers its eyes, and for that reason 
it is called Pout, Bib, Blens, Blinds. Tho anus is in a line under the 
origin of the pectoral fin. The end of the rays of the tail are nearly 
square. It has a dark spot at the origin of the pectoral fin. The Bib is 
the deepest gadid. The fin-formula given by Yarrell is—1 D, 11; 2 D, 
20,0), 16; 1 A, 33; 2 A19; PIS: V,6. Vertebra, 48. 
G. minutus has, according to this author, the following fin-formula :— 
ei Dy ioe 3 DP hts WA on 2 A 17s. B, 14; Vi. 6. 
At different times the identity of the two species, G@. minutus and G. 
luscus has beer. maintained. This is the view which Smitt maintains in 
the last edition of the “Scandinavian Fishes,” although plates showing 
perfectly characteristic Juscus and minutus are included in the work. 
According to this author, Steindacher had asserted that the depth of the 
fish is merely a character of age, and he referred to the same category the 
character derived from the union of the anals in /wscus and their separa- 
tion in minutus. The comparative depth of the two species is certainly 
not a character that can berelied upon. But the deficiency in the second 
character mentioned I have not been able to find in the adult. Schmidt 
found this a very reliable character in the very young stages. Further, 
Smitt remarks that ‘‘the size of the eyes has been long since ascertained 
to undergo a relative diminution with increasing age.” The relative size 
of the eyes in /uscus and minutus is not of much importance. 
Smitt has compared 5 minutus and 3 luscus with respect to a large 
number of characters. In a considerable proportion of these very close 
agreement is found between the two species. That is to be expected, 
since luscus and minutus resemble one another closely ; in fact they form 
a small group of two fishes very distinct from the other Gadids. The 
following are the characters which Smitt selected :—Length of the head ; 
distance of the beginning of each of the three dorsal fins from the tip of 
