BEARDED COTTUS OR ARMED BULLHEAD. 
209 
orbit. The jaws are armed with extremely tine, coni- 
cal and straight teeth, with the points somewhat re- 
curved, and set in several irregular rows, thus forming 
fairly broad bands (cards). The two upper pharyngeal 
cards are round, the two lower triangular, all four being 
composed of very small teeth. The gill-openings of 
average size. The preoperculum, the surface of which 
is generally striated, is almost twice as high as broad 
(long), and at the lower posterior corner is furnished with 
a spine, pointing in a backward direction and generally 
recurved. The operculum is also striated in most cases, 
is of small size and irregular, triangular form, with 
its longest corner pointing downwards, and bears supe- 
riorly a blunt, longitudinal ridge. The nostrils are 
arranged as in the preceding species, and here too, the 
posterior one on each side is so small that it is to be 
distinguished only with difficulty. The eyes, which are 
set high, are smaller than in the preceding species, the 
diameter being less than the least breadth of the inter- 
orbital space. The distance between them and the tip 
of the snout is less than that between them and the 
gill-openings. We sometimes tind round the iris a ring 
of dermal tubercles, especially well-developed and raised 
in a conical shape on the lower part of its margin. 
The superior margin of the orbit forms a raised, blunt 
ridge, which is sharper and even furnished with spines 
during youth. From this ridge run two bars, diverging 
posteriorly, the inner of which ends in a protuberance 
corresponding to the ordinary occipital spine of the 
Cotti, while the outer runs across the squamosal bone 
and ends in an obtuse spine, at the hind point of the 
posttemporal bone. The suborbital bones are elongated; 
the lower part of the anterior one is furnished with 
three transverse ridges, with depressions between them 
which contain the muciferous cavities and pores be- 
longing to the system of the lateral line; and the 
posterior, which is larger and is united to the pre- 
operculum, is square in form and has a bony spine, 
pointing in a backward direction, at the middle of the 
raised lower margin. The spines of the head are thus 
8 in number — four on the tip of the snout and two 
on each side of the head, the anterior on the suborbital 
bone and the posterior on the preoperculum. On the 
head we also find a number of short barbels, which 
are characteristic of this species, and the arrangement 
of which is given in the specific description. 
The body is covered with plate-like scales, furnished 
with an edge or compressed elevation, which in most 
cases, at least among young specimens, ends in a more 
or less sharp point, which extends back over the margin 
of the next scale. These plates are set in regular rows, 
which form longitudinal ridges or edges. The back 
and a part of the sides are covered by two rows, the 
plates of which, especially the anterior by the occiput, 
are larger than those of the other rows, and the anterior 
ones, especially in old specimens, without any spine. 
These two rows, each of which is made up of about 
20 plates — four of which lie in front of the first 
dorsal fin, two, one or none between the two dorsal 
fins, and seven or eight along the base of the second 
dorsal fin — form a furrow along the back, are broad 
anteriorly, and gradually decrease in breadth towards 
the second dorsal fin, at the end of which, when it is 
depressed, they unite and from this point to the base 
of the caudal fin form only one row, containing about 
12 plates". Under the belly there are two rows, with 
about 20 plates in each, and in extent and position 
analogous to those on the back. They unite at the 
end of the anal fin, forming from this point to the root 
of the caudal fin a simple row of 12 plates. This 
union of the rows of plates, both on the back and on 
the belly, renders the anterior part of the body octa- 
gonal, the posterior hexagonal. Between the rows de- 
scribed there are two others, parallel to them, on each 
side of the body; the upper consists of about 27 plates, 
begins at the end of the pectoral fin, and extends in 
a straight line from this point to the base of the caudal 
fin; the lower begins at the insertion of the pectoral 
fin, consists of about 34 plates, and also ends at the 
base of the caudal fin. Besides these regular rows of 
plates, there are other smaller, convex, rounded plates, 
on some parts of the body, e. g. in front of the pec- 
toral fins and round the vent. The lateral line, the 
scales of which, like the plates, gradually diminish in 
size as they approach the caudal fin, runs along the 
middle of the body, rises slightly above the pectoral 
fins, and from the end of these fins runs in a straight 
line to the caudal fin. The vent lies well in front, 
at the end of the first quarter of the length of the 
body. 
The first dorsal fin is almost triangular, with 
rounded apex, and contains five or six simple rays, the 
° The number varies between 9 and 13; on the anterior ones the top of the ridge is longitudinally divided. 
Scandinavian Fishes. 
