TADPOLE FISH. 
561 
Its depth (the length of the longest rays) is about 9 
or 10 % of the length of the body. 
The anal tin is of the same form and the same 
extent in a backward direction as the second dorsal; 
but the interval between this tin and the caudal tin is 
sometimes more distinct, though only inconsiderable, 
and the tin is shorter. The distance between the tip 
of the snout and the beginning of this tin is 37 — 38 % of 
the length of the body in young specimens, 40 — 43 % 
in old, and its base usually measures about 45 % of 
the length of the body. 
The caudal tin is comparatively small, with narrow 
base and expanded, rounded hind margin. In young 
specimens the length of its middle rays is about 12 % , 
in older ones 10 — 9 1 / 2 % , of the length of the body. 
The entire coloration of this fish is very monoto- 
nous, of a deep brownish black with a bright and 
handsome, blue lustre, which throws brilliant lights on 
the smooth surface of the body. The skin of the 
mouth and the grooves which receive the upper jaw 
and the labial skin, are whitish. The iris is yellowish, 
and the pupil has a blue lustre. The tins are of the 
genera] colour of the body, but the free tips of the 
ventral rays, the extreme margin of the whole of the 
second dorsal fin, of the beginning of the anal tin, and 
of the top of the caudal tin are whitish. After the 
death of the fish, the colours fade and turn reddish, 
and the lustre disappears. A young specimen 13 mm. 
long which Malm caught on the 23rd of July, 1875, 
in Lunnevik (Gaso, Bohuslan), was entirely whitish, 
with the exception of the ventral fins, which were deep 
black, while a blackish brown pigment also appeared 
on the head, the front part of the sides, and across 
the occipital region. Still, the typical form of the species 
was already developed. 
In its internal structure the Tadpole Fish essentially 
resembles the Cods, and the abdominal cavity extends 
some way, though not very far, behind the beginning 
of the anal fin. But the character that sharply separ- 
ates this fish from most of the preceding genera, is 
that- the numerous pyloric appendages of the other ge- 
nera are here wanting. The Tadpole Fish is furnished 
merely with two (sometimes only one) short projections 
or expansions of the intestine, rudimentary traces of 
these appendages, and occupying the same position. 
The air-bladder is divided into two parts, the anterior 
larger and more expanded in a lateral direction than 
the posterior. 
On account of its black colour the Tadpole Fish is 
known at some spots in the island-belt- of Bohuslan as 
Smed (Blacksmith) and Bldckfisk (Ink-fish). It is also 
called Matfar (Breadwinner), Paddal (Toad Eel), and 
Hulekolja (Cave Haddock). In the Sound, according to 
Schagerstrom, it bears the name of Hcifpaddci (Sea Toad). 
The geographical range of the Tadpole Fish ex- 
tends from the neighbourhood of Trondhjem to England, 
Ireland, and the coasts of the Channel, but on the north- 
west coast- of France, according to Moreau, it is ex- 
tremely rare. It is no common fish on the English 
coast either, and seems, therefore, t-o be really Scandi- 
navian. It occurs both on the Norwegian coast and on 
the coast- of Bohusliin as Avell as throughout the Catte- 
gat-. From the last- locality it- occasionally enters the 
Sound and Ise Fjord, and passes through the Belts 
down to the neighbourhood of Kiel and the coast- of 
Mecklenburg. On the Baltic coast of Scania, however, 
this species has not- been found. 
Its habits probably resemble those of the preceding- 
genus, and it- is usually found in solitary specimens at 
rather shallow spots (in 5 — 12 fathoms of water, ac- 
cording to Malm), among the seaweed at- the bottom. Off 
Kullen, however, according to Nilsson, it sometimes 
happens, in late autumn, that three or four specimens 
are taken in one and the same Cod-net. Otherwise it 
is caught only by accident in every kind of fishing- 
tackle, such as lobster or crab pot-s etc., but on the 
coast- of Bohuslan, according t-o Flies, oftenest- on 
Haddock-lines, when these are set during autumn at 
shallow, weedy spots for the so-called Grass Cod. That 
it- also descends to greater depths is shown by a large 
specimen which Mr. C. A. Hansson has forwarded to 
the Royal Museum, and which was taken at a- depth 
of 40 or 50 fathoms in St-romst-ad Fjord. 
Its food is composed of all kinds of lower marine 
animals, such as crustaceans, mollusks, worms, and 
especially Ecbinoderms (sea-urchins and star-fish), frag- 
ments of which have been found in its stomach and 
intestine. But- it is by no means averse to fish, for in 
two of the specimens we have examined we found the 
stomach in each case to contain the head of a. small 
Herring. 
Nilsson was told at Kullen that the Tadpole Fish 
spawns between Martinmas and Christmas, but- this is 
probably an exception to the general rule. In the month 
of July Fries observed on the coast- of Bohuslan 
two Tadpole Fish that kept close to each other, and, 
Scandinavian Fishes. 
71 
