EEL TRIBE. 449 



at a minimum 1650 tons, with a total value of £130,000. It is almost superfluous 

 to mention that eels pass the greater portion of their time when in fresh water 

 buried in the mud, from which they issue forth at night to feed. During the cold 

 of winter large masses of them are not unfrequently found tightly coiled together 

 for the sake of mutual warmth. The largest species occur in the islands of the 

 South Pacific and New Zealand, where they inhabit lakes ; specimens from these 

 regions having been recorded to measure from 8 to 10 feet in length. 



Resembling the true eels in the presence of pectoral fins, in the 

 tail being surrounded by the median fin, and the free tongue, the 

 gigantic marine forms known as congers differ in being scaleless, in the deep cleft 

 of the mouth, in the presence of a set of teeth on the outer sides of the jaw placed 

 so close to one another as to form a cutting edge, and by the dorsal fin commencing 

 at a point just behind the base of the pectorals. The common conger {Conger 

 vulgaris), which may grow to a length of 8 feet, appears to be almost cosmo- 

 politan in distribution, being as abundant in the seas of Tasmania as it is in 

 British waters. Congers feed chiefly by night, and prey upon crustaceans, cuttles, 

 and various kinds of fish, such as pilchards and herrings. Their favourite resorts 

 are either hollows or crevices in the rocks, or sandy bottoms, in which they can 

 bury themselves ; and in such situations they are sometimes left by the ebbing 

 tide. The flesh of these eels is of a highly gelatinous nature, and is said to be 

 largely employed in soups. Three other species of the genus are known, one of 

 which is abundant in the Indian Ocean. 



Among the numerous other generic modifications of the family, 

 Serpent-Eels. & e . J 



we select for notice the serpent-eels (Ophtchthys) as an example of a 



group in which the extremity of the tail is free, the nostrils are situated at the 



extremity of the muzzle, and the tongue is fixed. Teeth are present on the 



vomers, those in the jaws being either obtuse, or pointed and arranged in a single 



series ; and whereas small pectoral fins are present in some species, in others they 



are wanting. Serpent-eels are represented by a great number of species, ranging 



over all tropical and subtropical seas, but none attaining any large size. The 



difference in the structure of the teeth of the various species may probably be 



taken as indicative of a difference in the nature of the food similar to that already 



recorded as obtaining among the muraenas. 



Only a few words can be devoted to the deep-sea members of 

 Deep-Sea Eels. . . ■"■ 



the family, which are represented by several genera. Among these 



are certain congers (Synaphobranchus) occurring in all oceans at depths of from 

 three hundred and forty to two thousand fathoms, and characterised by the gill- 

 openings being united into a single longitudinal slit on the under surface of the 

 body between the pectoral fins ; the gape being very wide, the teeth small, and the 

 body scaled. In these forms the muscular system is well developed ; but in another 

 genus (Saccopharynx) it is extremely feeble, except on the head, and the bones 

 are soft and spongy. The head and gape are of immense size ; the muzzle is short 

 and flexible ; the weak jaws are armed with long, slender, curved teeth, placed at 

 intervals ; and the gill-openings are wide and situated on the lower part of the 

 sides at some distance from the head, the narrow gills being free and exposed. 

 The long and band-like tail ends in a long tapering filament, and the dorsal and 

 vol. v. — 29 



