23,2 H err e: Philippine Eels 141 



These eels are found at moderate depths in most warm and 

 temperate seas and estuaries, and also enter brackish and fresh 

 water. All the species are plainly colored, grayish, dusky, 

 or brownish above and pale or silvery beneath. 



Like the Anguillidse and some isospondylous fishes, the conger 

 eels undergo metamorphosis. When hatched they are strange- 

 looking, elongate, transparent, ribbonlike animals with minute 

 head and very tiny mouth. With advancing age the body 

 becomes smaller as the tissues are compacted until after a year 

 or so they assume the general form of the adult. 



Key to the genera of Leptocephalidx. 

 a 1 . Anterior nostrils in a tube. 



ft 1 . Origin of dorsal over or behind middle of pectorals.... Leptocephalus. 

 6*. Origin of dorsal above, before, or slightly behind base of pectorals. 



a\ Anterior nostrils not tubulate. Dorsal beginning over or behind base 

 of pectorals; tail strongly tapering, very long, and whiplike. 



TTroconger. 



Genus LEPTOCEPHALUS Scopoli 

 Leptocephalus Scopoli, Int. Hist. Nat. (1777) 453. 

 CONGER EEIS 



Large and powerful marine eels, which strongly resemble 

 Anguilla in general appearance but lack scales, the elongate 

 body becoming much compressed posteriorly. Vertical fins well 

 developed, confluent with caudal, origin of dorsal above the well- 

 developed pectorals. Head of moderate size, depressed, often 

 flat above eyes, pointed; eye large, covered by skin; posterior 

 nostrils opposite upper or middle part of eye, anterior nostrils 

 in short tubes near tip of projecting snout; mouth extending to 

 middle of eye or beyond, lips thick and large; tongue free. 

 Teeth small, those in outer series in both jaws equal, compressed, 

 and close-set, forming a cutting edge; the inner series incomplete 

 or partially developed or even absent, of small conical teeth; 

 teeth on vomer arranged in a short conical band the point of 

 which is directed backward; no canines. Lateral line present. 

 Gill openings large, extending from pectorals downward. The 

 skeleton differs much from that of Anguilla; vertebrae about 

 56 -f 100. ,.* „ 



This genus includes the well-known and almost cosmopolitan 

 conger eel and a few closely related species. Some representa- 

 tive of the genus is found in nearly all temperate and tropical 

 seas. I have been unable to learn of any distinctive names 



