45(j 



CONTRIBUTION TO THE 



li. No pectoral fins ; no metapterygoid ; pterygoid a slender rod ; ethmoid much wider. Oymnothoracidce. 



Coloobphali. Parietals largely in contact, opercular bonos rudimental, the preoperculum generally wanting. 

 Promaxillary rudimental or wanting; ethmoid very wide. Symplectic, maxillary, pterygoid, basal-branchihyal, 

 .superior and inferior pharyngeal bones all wanting, except the fourth superior pharyngeal. This is j aw-like, and 

 supported by a strong superior branchihyal ; other superior branohihyals wanting or cartilaginous. 



This well marked order includes the eels of tbo family Murmnidm (with Qymnomurmna etc). 



It is evident from the above, that the eel-like form common to the last five orders is not more important in a 

 systematic sense, than the fish-like form, which is common to so many of the others. 



Physoclysti. 



The following is an analytic synopsis of the orders. They all have the parietals entirely separated by the supra- 

 occipital, and lack the prsecoracoid, and have the symplectic present.* 



A Scapula suspended to the anterior vertebrae. 

 Superior branohihyals and pharyngeals present, inferior distinct ; maxillary distinct ; no interclavicles. 



15 QPISTOHMI. 



A A Scapula suspended to cranium by a posttemporal. 

 I. Ventral lins abdominal. 



Branchial arches well developed, the hones present, except fourth superior pharyngeal; third much enlarged. 

 Inferior pharyngeals distinct. 10 Peecksoces. 



Third and fourth superior pharyngeals much enlarged, inferior pharyngeals coossifled. 



17 Synkntoonatiii 



Superior branohihyals and pharyngeals reduced in number ; inferiors separated in Hemibeanchii. 



Superior branohihyals and pharyngeals, and basal branohihyals wanting; gills tufted. 



1!) LoPHOBBANCHII. 



If. Ventral lins thoracic or jugular, 

 first vertebra united to cranium by suture ; epiotics united behind supraoccipital ; basal peooral radii elongate. 



1(1 Pediculati. 

 Posterior cephalic region normal, anterior twisted SO as to bring both orbits on one side; inferior pharyngeals 



distinct. 21 Heteeobomata. 



Cranium normal, premaxillaries usually coossifled with the maxillaries bellied, and the dentary with the articular ; 

 pharyngeal bones distinct. 22 PlECTOGNATHI. 



Cranium normal, bones of the jaws distinct ; inferior pharyngeal bones distinct. 



21! Pebcomoephi. 



Cranium normal, bones of the jaws distinct ; third superior pharyngeal much enlarged , articulated with cranium , 

 inferior pharyngeals coossifled. 24 Phabyngognatbi. 



These orders arc more fully defined below, and I ho families which are referable to l hem pointed out. 



Opisttiomi. Scapular arch suspended to the vertebral column. Superior pharynegcals and branohihyals ossified, 

 in the former third a little larger, followed by a small fourth. Three basal branohihyals, inferior pharynegcals distinct 

 Maxillary bone distinct; supraoccipital separating parietals. No interclavicles. Symplectic present. 



One family the MtwUicemhelidtr. In it, the tail is isocereal, spinous dorsal present, and the ventrals wanting. 



It bears considerable resemblance to the eels of the family Symbranchidas. 



Peecesoces. Ventrals anteriorly or posteriorly abdominal. Mouth formed by premaxillaries; posttemporal 

 furcate anteriorly, not suturallj attached. Three basal branchihyals : all those of the superior series generally pres- 

 ent. Superior pharyngeals with the third very largely developed, but not articulated to the cranium. Inferior pha- 

 ryngeals distinct. Basal pectoral rays four, short. Basis cranii without muscular tube, but with rudimental upper 

 floor. 





* Except in Oatradum, where it is not OBsltted. 



