1396 Bulletin 4.7, United States National Museum. 



pp. Head very broad above, the interorbital 

 space flattish, excessively cavernous, 

 the septa reduced to thin partitions; 

 soft dorsal and anal fin usually densely 

 scaly; second spine of dorsal usually 

 thickened. STELLIFER, 581. 



II. Gill rakers comparatively short and thick, usually not longer 

 than posterior nostril; anal fin inserted farther forward ; 

 snout above lower jaw with large pores, and with two 

 more or less distinct slits on its edge, these sometimes 

 obsolete; preorbital more or less broad; mouth more or 

 loss inferior. 



v. Preopercle with its bony margin armed with strong per- 

 sistent spines which do not disappear with age; cau- 

 dal fin not lunate, the middle rays longer than the 

 lower. OPHIOSCION, 582. 



vv. Preopercle with its bony margin serrate in the young, 

 becoming entire with age ; caudal fin truncate or lu- 

 nate, the middle rays not longest; slits and pores of 

 upper jaws well developed. SOUENOPS, 583. 



vvv. Preopercle without bony serratures, its membranaceous 

 edge entire or crenate, or fringed; slits and pores of 

 upper jaw well developed. SCI^ENA, 584. 



Tck. Lower pharyngeals very broad, with coarse blunt molar teeth ; 

 teeth in both jaws subequal, in broad bands; preopercle with its 

 bony margin coarsely serrate; lower jaw included; snout with 

 pores and slits as in Scicena -, gill rakers rather short and slender. 



RONOADOR, 585. 



jj. Teeth very small, subequal, those in the lower jaw wanting or decidu- 

 ous ; lower pharyngeals rather broad, with paved teeth; mouth 

 smajl, inferior; snout as in Scicena; preopercle entire; anal fin 

 long, with about 12 soft rays ; gill rakers shortish, rather slender. 



LEIOSTOMUS, 58G. 



hh. Lower jaw with one or more barbels, either at the symphysis or on the rami; 

 snout with slits and pores as in Scicena; lower jaw included; preorbital 

 broad; lower teeth in villiform bands; gill rakers more or less short. 

 w. Pseudobranchioi well developed ; pectoral fin not elongate. 



x. Lower jaw with slender barbels, usually several in number. 



y. Barbels mostly in a tuft at the symphysis of lower jaw; mouth 

 very small, inferior; gill rakers minute, thickish; dorsal 

 spines XorXI; preopercle sharply but finely serrate; pre- 

 orbital turgid and cavernous, more or less translucent; 

 caudal fin rhombic. (Fluviatile species.) PACHYPOPS, 587. 

 yy. Barbels chiefly lateral, along the rami of the lower jaw, usually 

 none at the symphysis; lower pharyngeals narrow, with 

 sharp teeth. 



z. Preopercle without bony seme; dorsal spines XIV; gill 

 rakers short, but rather slender. GENYONEMUS, 588. 

 zz. Preopercle with its bony margin armed with strong teeth ; 

 dorsal spines X or XI; gill rakers short, thickish. 



MlCROPOGON, 589. 



xx. Lower jaw with a single thickish barbel at its tip. 



'. Air bladder large; anal spines 2 ; back more or less elevated; 

 preopercle with its bony margin crenate or serrate; pec- 

 torals short, shorter than ventrals. (Free swimming 

 species.) FMBRINA, 590. 



