382 Mr. 0. T. Eegan on the Osteology and 



snout ; teeth cardiform, in bands ; nostrils lateral ; gill- 

 openings well separated ; pharyngeal apertures of branchial 

 clefts restricted ; pharyngeals ovate or oblong, covered with 

 small teeth. Frontals paired ; suspensoriuui vertical ; palato- 

 pterygoid very slender, not laminar. 4 pectoral radials. 

 Neural spines long and slender j caudal vertebrae without 

 transverse processes. 



Myroconger compressiis, from St. Helena, appears to be 

 quite as closely related to the Anguillidae as to the Mursenidse* 



Family 6. Muraenidse. 



Naked, compressed or cylindrical ; vertical fins variously 

 developed; no pectorals. Mouth terminal, with lateral cleft 

 extending behind eye; maxillary articulated with ethmo- 

 vomer at some distance from end of snout ; teeth strong, 

 acute or obtuse, in one or more series; nostrils lateral ; gill- 

 openings well-separated; pharyngeal apertures of branchial 

 clefts restricted ; upper and lower pharyngeals bearing 

 strong curved teeth in a double series, elongate, supported 

 by the enlarged epi- and ceratobranchials of the fourth arch. 

 Frontals pilired ; hyomandibular with broad head; palato- 

 pterygoid very slender, almost vestigial. Neural spines 

 developed in caudal region only, short, laminar; caudal 

 vertebrse with lateral transverse processes. 



Murcena, Gymnothorax, Echidna, Strophiodon, Thyrsoidea^ 

 lilmiomurcena, Muroinohlenna, Chatmomurcena, Enchelyckoref 

 &Ci, from tropical and temperate seas. 



Family 7. HeterenchelidaB. 



Naked, cylindrical, with the tail much longer than the 

 trunk ; vertical fins well developed only towards the end of 

 the tail j pectorals absent. Mouth moderate, with lateral 

 cleft extending behind the very small eye ; maxillary articu- 

 lating with ethmoid near end of snout ; teeth conical, biserial ; 

 nostrils lateral ; gill-Oj)enings separate; pharyngeal apertures 

 of branchial clefts wide ; pharyngeals oblong or ovate, 

 covered with small teeth. Heart just behind the gills. 

 Frontals paired, anteriorly with stiongly developed mucous 

 channels ; vomer distinct, united by suture with ethmoid ; 

 orbitosphenoids long and narrow, separating parasphenoid 

 from frontals ; prootic and basioccipital swollen to form a 

 thin-walled bulla containing a large otolith. Suspensorium 

 vertical ; palato-pterygoid a rather broad lamina. Neural 



