Order SYNBRANCHOIDEA. 



Body anguilliform. Scales absent or minute, longitudinally 

 arranged. Lateral line present. Skull long, the supraoccipital 

 separated from the frontals by the parietals, which are meeting 

 [not in Alabes\ Mouth not protractile, bordered above mainly 

 by the intermaxillaries; the maxillaries lying behind and 

 parallel to them. Opercular bones normal. Anterior vertebrae 

 not modified, no Weberian ossicles. Pectorals absent, only the 

 membrane bones of their arch are developed. Ventrals absent, 

 only in Alabes Cuv. present as jugular rudiments. Dorsal and 

 anal rayless folds of the skin, united with the small caudal, 

 which has a few rays. Teeth in bands or in series on jaws 

 and generally on palatines and pterygoids. Gillmembranes con- 

 fluent, free from isthmus or united with it and accordingly 

 forming a single aperture pierced under the throat and common 

 to both sides or this aperture is only superficially a single one. 



i. Fam. SYNBRANCHIDAE. 



Elongate. No scales. Anus in posterior half of the length. 

 Ventrals absent. Gills on three or four branchial arches, well 

 developed or rudimentary. 



Distribution: Indo-australian Archipelago, Dampier Archi- 

 pelago, Philippines, Japan, Asiatic continent from Indian 

 Peninsula to Northern China, tropical parts of West Africa 

 and Central and South America. 



Key to the genera of Synbranchidae. 



I. Gillmembranes confluent and attached to isthmus by a 

 median septum which divides the gillopening. Gills on 

 three arches, rudimentary. Teeth in bands Monopterus p. 412. 



