53. ANGUILLID^. 357 



■with subalternate large white and black spots ; anal (and dorsal) with 



a broad black margin. {Gunther.) Florida and Texas southward. 



{Gymnothorax ocellatus Agassiz, Spix Pise. Brasil, 91; Giiutlier, viii, 10:i: Ncomurwna 

 nigromarginata Girard, 17. S. Mes. Bound. Surv. Iclitli. 7G.) 



Family LIIL— ANGUILLID^E. 



{The True Eels.) 



Body elongate, serpentiform, naked or covered with Imbedded scales. 

 Head conical, the snout not much produced, sometimes very blunt. 

 Preoperculum present. Premaxillaries present, separated on the me- 

 dian line hy the ethmoid. Maxillaries wanting or connate with the 

 premaxillary, which forms the border of the mouth. Superior branchi- 

 hyals and inferior and superior pharyngeals well developed, the latter 

 of three bones. Teeth various. Gill-openings separate, not very small 

 (except in Simenchehjs). Ventral fins none; dorsal and anal low, usually 

 confluent around the tail; pectorals generally present, i)laced rather 

 high. Yent not for from anal fin. Skeleton ossified. INIuscular system 

 well developed. Heart not far behind gills. As here understood, this 

 family includes a wide variety of forms, which have been often arranged 

 in several families. It is probable that some division will be found nec- 

 essary, but we have not the data on which to make it. Genera about 

 20; species about IGO. In all warm seas, many of them ascending 

 rivers. 



(AnguilUdcB, part; Gtbr. viii, 23-90.) 



a. Tongue not free anteriorly. 



b. End of tail not surrounded bj"- the fin; nostrils labial. (Oplnsurince.) 

 c. Pectoralfins wanting (rarely rudimentary); teeth small, conical. CcECULiV, 169. 



cc. Pectoral fins present ; teefh acute Opuichthys, 170. 



hb. End of tail snnounded by the fin. 

 d. Nostrils labial. (Mi/riiiw.) 



e. Teeth granular MYRiciixnYS, 171. 



dd. Nostrils superior or lateral. (MuraneaoeincB.) 



f. Pectoral fins present; dorsal and anal rudimentary Neoconger, 17'2. 



aa. Tongue fx'ee anteriorly ; pectorals present ; nostrils not labial. 

 g. Suout snbcouical. 



h. Body scaleless. {Congrincv.) 

 i. Jaws with an outer series of close-set teeth; lower jaw not pro- 

 jecting Conger, 173. 



hli. Body with rudimentary, linear, imbedded scales, arranged at right 

 angles with each other. (AnguilUnce.) 



j. Teeth in bands; lower jaw projecting i\:NGUlLLA, 174. 



gg. Snout very short and blunt ; body scaly ; mandible very strong. 

 (Slmcnchch/incv. ) 

 k. Teeth blunt, incisor-liho in one series; gill-opening a very 

 short longitudinal slit Simencuelys, 175. 



