BURBOT. 
535 
other fishes that have a distinct caudal fin. On ac- 
count of the thick integument they are difficult to count. 
The length of the middle rays varies between about 6 
and 7 % (sometimes 8 or 9 %) of that of the body. 
The anal fin begins at a distance from the tip of 
the snout equal to about 45 — 48 % (sometimes 49 or 
even nearly 50 %) of the length of the body, and the 
length of its base measures about 45 — 47 % (sometimes 
42 or even 41 %) of that of the body. Its rays, gener- 
ally about 70 rt in number, are of the same structure 
as those of the second dorsal fin, but their height is 
only 3 f i of that of the latter. 
The pectoral tin is large and rounded. It usually 
measures 2 / 3 of the length of the head, but in one spe- 
cimen we have found it almost as long as the whole 
head. It is generally made up of 18 — 20 rays. Often, 
however, according to Sundevall, there are 22 rays on 
one side or on both, and sometimes, according to Khoyek, 
only 17. At about the 7th or 8th ray we find 3 or 4 
of the same length. The anterior and posterior rays 
grow gradually shorter. The first is simple, and gener- 
ally half the length of the fin. 
The insertion of the ventral fin lies entirely in front 
of the base of the pectoral fin. The rays are 6 or 7 
in young Burbot, but in old ones quite as often 8. The 
second ray is soft and thick, 1 / i longer than the others, 
and somewhat separated from them. In young speci- 
mens it is almost as long as the pectoral fin, in old 
ones distinctly (as much as 1 / 4 ) shorter. The first ray 
is as long as the third and free at the tip. 
The coloration, which is densely variegated with 
yellow and black, intensifies in a high degree fhe re- 
pulsive, Amphibian-like appearance of this fish. It is 
extremely variable, however: sometimes plain, dark 
blackish gray, sometimes lighter with only small spots 
of black on the upper part of the body. The relation- 
ship to the Ling is expressed by the collection of the 
black pigment into a more or less continuous band along 
the margins of the vertical fins. In spite of all the 
irregularity in the distribution and confluence of the 
spots we can generally trace a longitudinal band on the 
cheeks and snout. The inner (hind) surface of the pec- 
toral fins is bluish. The belly and the ventral fins are 
generally pale and whitish, but sometimes only slightly 
lighter than the sides of the body. The fry seem al- 
ways to be of a plain, dark colour. 
Of the internal organs we may give the following 
particulars. The liver is rather large, reddish white, 
set on the left side, and undivided. A rather small lobe 
projects on the right side and covers the gall-bladder''. 
The peritoneum is white. The stomach, which forms 
an immediate continuation of the oesophagus, extends 
along only slightly more than 2 3 of the abdominal ca- 
vity, and is furnished internally with 7 large longi- 
tudinal folds, which disappear when it is distended. 
Only one side, the side from which the pyloric part 
starts, is smooth and contains small, dense, digitate 
glandules, hardly a millimetre in breadth. The pyloric 
part originates on the under side of the stomach, in a 
line with the tip of the liver, not far from the bottom 
of the stomach. It is small and narrow, but thick- 
walled and firm. It is continued in a forward direction 
by the intestine, which at the very beginning has two 
bunches, one on each side, of 20 — 24 appendages, ir- 
regularly united at the base into a smaller number of 
.ducts. The intestine soon bends back to the anal region, 
whence it returns forward, again to bend back to the 
vent. It is of uniform thickness, only the last portion 
(the rectum) being somewhat wider, closed by a valve 
(like a rnlvula coli), and furnished internally with five 
or six, not very distinct, longitudinal folds. The spleen 
lies at the hind part of the middle coil of the intestine. 
The ovaries are coalescent behind, with a common ori- 
fice, which opens behind the vent. They are hung in 
a distinct mesenterium or fold of the peritoneum. The 
ripe eggs are flame-yellow and rather small, 0‘8 — 1 mm. 
in diameter, but exceedingly numerous, forming a mass 
of considerable size. Hermaphrodites are not so very 
rare; one specimen of this kind was described as early 
o 
as 1800 by Professor Pipping of Aboh The air-bladder 
is fairly large and firm, lying close to the spinal column. 
It is somewhat compressed at the middle, grows wider 
anteriorly, and ends in front in two lobes, or with two 
obtuse corners or short ramifications, which occupy the 
anterior elongations of the abdominal cavity beside the 
dorsal column and the occiput. The kidneys form a 
fairly large, roundish, gray-brown reddish mass behind 
the air-bladder and the vent. They have only small. 
“ In one young specimen, however, we have counted 89. 
b According to Bean (1. c.), Dall found in male Burbot from Alaska two or even three, distinct gall-bladders, opening into a com- 
mon gall-duct. 
c Vet.-Akad. Hand!. 1800, p. 33, tab. I, fig. 1. 
