83 FISH.E8. 



CLASS IV. PISCES. FISHES. 



Animals inhabiting waters, furnished with gills for the 

 purpose of breathing, and fins for swimming. 



ORDER I. APODES. 



Bony fishes, without ventral fins, 



1. An gu ill A. Head smooth: nostrils tubular : eyes co- 



vered with the common skin : gill-membrane 10- 

 rayed: body roundish, smooth, mucous : dorsal, caudal 9 

 and anal-fins united : spiracles behind the head or 

 pectoral fins. 



2. Ophis. Habit of the Anguilla, but the tail is without 



fin at the end, causing the dorsal and anal fins to be 

 distinct. 



3. Anarichas. Head rounded, obtuse: front-teeth in 



each jaw, 6 or more in number, conic, strong, diver- 

 gent : grinders in the lower-jaw and palate, rounded : 

 gill-membrane 6- rayed : body roundish : caudal-fin 

 distinct. 



4. Ammodytes. Head compressed, narrower than: the; 



body ; upper-lip doubled ; lower-jaw narrow, 

 pointed : teeth small, very, sharp : gill-membrane 

 7-rayed : body long* square, rounded at th& sides, 

 with very minute scales : caudal-fin distinct. 



5. Ophidium. Head somewhat naked : teeth in the 



jaws, palate, and throat : gill-membrane 7-rayed : 

 body ensiform. 



6. Leptocephalus. Head small, narrow: body very 



thin and flat : pectoral fins none. 



7. Xiphias. Head with the upper-jaw ending in a long 



sword-like projection : month without teeth : gill- 

 membrane 8-rayed : body roundish, without apparent 

 scales. 



ORDER II. JUGULARES. 



Bony fishes, with the ventral fins placed before the pectoral. 



8. Callionymus. Upper-lip doubled up : eyes vertical, 



approximate : gill-covers closed, with a small aper- 

 ture each side the neck; the membrane 6-rayed : 

 body naked : ventral-fins very remote. 



9. Trachinus. Head compressed, a little rough : gill- 



membrane grayed; the covers prickly, the lower 

 piece serrate : body compressed : vent near the 

 breast. 



10. Gadus. Head smooth: gill-membrane with 7 cylin- 

 drical rays : body oblong, clothed with deciduous 



