43 § 
SOFT-FINNED GROUP. 
Snake-Fishes. 
Parasitic Fish. 
The typical genus Ophidium, constituting, with an allied form, 
the second subfamily, has the pelvic fins replaced by a pair of barbel¬ 
like filaments; the elongated and compressed body being covered with very 
minute scales, while the eyes are medium, and the teeth small. The few species of 
this genus range over the Atlantic and Pacific. In the South American, South 
African, and Australasian seas there occur three much larger but nearly allied fishes, 
which have been referred to a second genus ( Genypterus ), on account of the outer 
row of teeth in the jaws, as well as those of the single palatine series, containing 
some enlarged tusks. These fish are of considerable commercial importance, and are 
known at the Cape as Jdipvisch, and in New Zealand as Cloudy Bay cod, or ling. 
Some half-score species of very small eel-like fishes, scientifically 
known as Fierasfer and Enclieliopliis, and inhabiting the Mediter¬ 
ranean, Atlantic, and Indo-Pacific, have an especial interest on account of their 
curious mode of life. They 
constitute a subfamily, readily 
characterised by the total 
absence of pelvic fins and by 
the vent being situated at the 
throat; and are parasitic in 
other marine animals, fre¬ 
quenting the hollows in the 
bodies of jelly-fish, the 
breathing-chambers of star¬ 
fishes and sea-cucumbers, and 
sometimes insinuating them¬ 
selves between the layers of 
the mantle of pearl-mussels 
or other bivalve molluscs. 
Occasionally they may become 
embedded in the substance of the shell of the pearl-mussel by the deposition of 
pearly matter over their bodies; an instance of this peculiar mode of preservation 
being shown in the accompanying illustration. 
The third subfamily is represented by the well-known sand-eels or 
launces—of which a British species ( Ammodytes tobianus ) is figured 
in the illustration—so abundant on sandy shores in Europe and North America, 
as well as by an allied genus from Madras. While agreeing with the preceding 
group in the want of pelvic fins, they differ in having the vent situated far back 
in the body ; and are further characterised by the great widtli of the gill-openings, 
the gill-membranes of opposite sides not being united. The lower jaw exceeds the 
upper in length, the dorsal fin occupies nearly the whole length of the back, and 
the anal is likewise elongated. The figured species, which is by far the commoner 
on the British coasts, generally measures from 5 to 7 inches in length, whereas the 
PARASITIC FISH EMBEDDED IN A PEARL-MUSSEL. 
(From Gunther, Proc. Zool. Soc ., 1886.) 
Sand-Eels. 
greater sand-eel (A. lanceolatus) may grow to a foot and a half. Sand-eels feed 
on marine worms and very small fish ; and when buried in the sand are captured 
in some parts of England by raking the sand with a long-pronged rake; their 
chief use being for bait. They are, however, by no means restricted to this kind 
