139G B2iUctin 4.J, United States National I\h(senvi. 



pp. Head very broad above, the interorbital 

 space flattish, excessively cavernous, 

 the septa reduced to tliin partitions; 

 soft dorsal and anal fin usually densely 

 scaly: second spine of dorsal usually 

 thickened. Stellifer. 581. 



II. ( i ill rakers coni])nratively short and thick, visually 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 mori' or 

 li\ss inferior. 

 V. Preopercle with its bony margin armed with stioiig per- 

 sistent spines which do not disappear wirti 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. Scli^nops, 583. 



vvv. Preopercle without bony serratures, its membranaceous 

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

 upper jaw well developed. Sci.kna, 584. 



Ik. Lower ])haryngeals very broad, with coarse blunt molar teeth ; 

 teeth in both jaws subequal, in broad l)ands; preopercle with its 

 bony margin coarsely serrate; lower jaw included; snout with 

 pores and slits as in Scicvna ; gill rakers rather short and .slender. 



EoxcADOit, 585. 



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



<ms : lower pharyngeals rather broad, with paved teeth ; mouth 



small, inferior; snout as in Scicena; preopercle entire; anal tin 



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



Leiostomus, 580. 

 ,ower 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. PseudobranchiiP well developed ; pectoral flu 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, thicki.sh; dorsal 

 spines XorXI; preopercle sharply but finely serrate; pre- 

 orbital turgid and cavernous, more or less translucent; 

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

 yil. I'.arbels chiefiy lateral, along the rami of the b)wer jaw, usually 

 none at the symphysis; lower pharyngeals narrow, with 

 sharp teeth. 

 z. Preopercle without bony serra? ; dorsal spines XLV; gill 

 rakers short, but rather slender. Genyonemus, 588. 

 7Z. Preopercle with its bony margin armed with strong teeth ; 

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



MiCROPOGON, 589. 

 XX. Low er jaw with a single thickish barbel at its tip. 



a'. 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. 



