EEL-TRIBE. LOPHOBRANCHII. 53 



by the skin, and of the absence of the dorsal fin (Fig. 262). It 

 is to the true Gymnotus, that the electric power is confined ; and 

 the group includes several other genera, of which some belong to 

 the British seas. Of these may be mentioned the Leptocephalus, 

 or Morris, which is a small riband-shaped fish, with a body so 

 thin and transparent that its internal structure can be seen with- 

 out dissection ; it lurks among sea- weeds, and is very lively in 

 its motions. The Avnnodytes^ or Launces, one of which is known 

 to fishermen by the name of the Sand -Eel, and another as the 

 Sand-Launce, are remarkable for their habit of burrowing in 

 the sand, in which they find the worms that constitute their chief 

 food. They become in their turn the prey of the Salmon ; to 

 whose support, whilst they are in the estuaries of rivers, the 

 Launces are believed to contribute largely. 



ORDER V. LOPHOBRANCHII. 



578. This order consists of a small group, which is separated 

 from all other Osseous Fishes by the structure of the gills ; which, 

 instead of hanging from the branchial arches in fringes of parallel 

 fibres, disposed like the teeth of a comb, are set upon them in 

 small round tufts, arranged in pairs. From this peculiar con- 

 formation, the name of the order, which signifies tuft-gilled, is 

 derived. The gills are defended by a large operculum, which is 

 attached by a membranous covering on all sides, except at one 

 part where a small hole is left for the escape of the water. These 

 fishes are also distinguished by having their body covered with 

 shields or small plates, which often give it an angular form. In 

 general they are of small size, and often without flesh. They 

 do not present many points of general interest ; but there are 

 certain peculiarities in their organisation, which are very interest- 

 ing to the Naturalist. In the Syngnaihus, or Pipe-fish, which 

 has a prolonged muzzle like that of the Fistularidas ( 566), the 

 eggs are not deposited as in other Fishes, but are conveyed 

 into a sort of pouch, formed by a doubling of the skin under the 

 body of the male ; this pouch is under the abdomen in some 



