of the Fishery Board for Scotland. ¥a7 
Colours and Scales.—The three species have silvery snouts, cheeks, and 
shoulders. 
Minutus has large silvery scales that are very easily rubbed off. The 
exposed part of the scale is covered with dark dots on a ground of silver. 
The overlapped part of the scale is colourless. The scales of the dorsum 
above the lateral line have a golden-yellow ground dotted with black. 
The golden-yellow colour is also seen on the silvery scales on the side. 
The scales of dwscus are smaller than those of minutus; they also are 
very deciduous. On the scale from the side of Juscus there is a broad 
edging of black dots. Beneath the scales the skin is thin and somewhat 
iridescent. When wet the skin of duscws has a slight golden sheen, but 
when dried the black-dotted scales give it a dirty black appearance. In 
large specimens preserved in formaline the appearance is silvery, but 
the skin has generally a blackish aspect. 
When preserved, minutus remains of a brownish-yellow colour, that is 
when the silvery scales are rubbed off, as usually happens. Where they 
remain attached the skin becomes of a dark appearance. The skin is of a 
rougher texture than that of duscuws. It is slightly pinkish on the dorsum. 
In both species the belly is silvery. £smarkii also is silvery on the 
sides. 
The Axillary Mark.—In luscus the axillary mark is a large blue-black 
patch covering the sides of the axilla, and extending out on the clavicle 
and over the hase of the pectoral fin. In minutus it is a small dark area 
on the axilla and the base of the first pectoral fin-ray. It does not 
extend on to the clavicle much. In esmarkii there is a very similar 
axillary mark to minutus: it isa collection of small black dots which 
spread over the base of the pectoral fin. 
The Peritoneum in esmarkii is black, and in preserved specimens the 
black layer shines through the thin abdominal wall. 
The Fins.—The anal fins of luscus are blue-black ; those of minutus 
yellow and black spotted. The first anal of minutus is sometimes very 
dark. 
Most of the unpaired fins of esmarhkii have a black border. Thus the 
anterior border of the first dorsal is black, while the superior and hind 
borders of the second and third dorsal fins are likewise black. The black 
parts of the second anal and caudal fins are the hind border and the hind 
half of the fin respectively. There are black spots along the bases of the 
fins, and also on the anterior border of the first anal. The anal fins of 
preserved specimens are without pigment, except on the anterior part of 
both fins, where a small area is covered with small dots. This character 
is more prominent in the larger specimens. The caudal fin is more or 
less all black. = 
The second and third dorsals are separate in minutus and in esmarktz, 
and are usually separate in /uscus. In one specimen of /uscus, however, a 
male measuring 16°8cm. in length, the second and third dorsals were united. 
The first and second anals are separate in minutus and esmarkiz, but 
are united in /usews. There is a thick integument on the unpaired fins in 
luscusand minutus. In the former the first anal is a thick flabby fin, the 
integument being soft and loose. This fin is often inflated with a gas, 
which can be pressed out at the edge. 
There is a characteristic difference between /uscus and minutus in the 
shape of the third dorsal and second anal fins, as will be seen by reference 
to Plate VIII. The hind edges of these fins in Juscus are cut straight 
across, at right angles to the longitudinal axis of the fish. In minutus 
the hind edges slope away posteriorly. In esmarkzi the slope is more 
pronounced and longer than in minutus (pl. ix.). 
