EELS. 671 



wanting in inorganic matter. Head and gape enormous. Snout 

 very short, pointed, flexible, like an appendage overlapping the 

 gape. Maxillary and mandibulary bones very thin, slender, 

 arched, armed with one or two series of long, slender, curved, 

 widely set teeth, their points being directed inwards ; palate 

 toothless. Gill-openings wide, at some distance from the head, 

 at the lower part of the sides ; gills very narrow, free, and ex- 

 posed. Trunk of moderate length. Stomach distensible in an 

 extraordinary degree. Vent at the end of the trunk. Tail band- 

 like, exceedingly long, tapering in a very fine filament. Pectoral 

 small, present. Dorsal and anal fins rudimentary. 



This is another extraordinary form of Deep-sea Eels ; the 

 muscular system, except on the head, is very feebly developed ; 

 the bones are as thin, soft, and wanting in inorganic matter, 

 as in the Trachypteridce. This fish is known from three 

 specimens only, which have been found floating on the sur- 

 face of the iN'orth Atlantic, with their stomachs much dis- 

 tended, having swallowed some other fish, the weight of 

 which many times exceeded that of their destroyer. It attains 

 to the length of several feet. 



Synaphobranchus. — Gill-openings ventral, united into a 

 longitudinal slit between the pectoral fins, separate internally. 

 Pectoral and vertical fins well developed. Nostrils lateral, the 

 anterior subtubular, the posterior round, before the lower half 

 of the eye. Cleft of the mouth very wide ; teeth small ; body 

 scaly. Stomach very distensible. 



Deep-sea Congers, with well-developed muscular system, 

 spread overall oceans, and occurring in depths of from 345 to 

 2000 fathoms. Four species are known. Probably attaining 

 to the same length as the Conger. 



Anguilla. — Small scales imbedded in the .skin. Upper jaw 

 not projecting beyond the lower. Teeth small, forming bands. 

 Gill-openings narrow, at the base of the pectoral fins. The dorsal 

 fin commences at a considerable distance from the occiput. 



Some twenty-five species of " Eels " are known from the 

 freshwaters and coasts of the temperate and tropical zones ; 



