91. SCI^NIDJE HAPLOIDONOTUS. 567 



cc. Teeth feeble, permanent in npper jaw only; anal spines small. 



LiosTOMUS, 297. 

 bb. Lower jaw with several minnte barbels. 



d. Preopercle with its membranaceous margin crenulate. 



Genyonemus, 298. 



dd. Preopercle with its bony margin serrate Mickopogon, 299. 



hbb. Lower jaw with a single thickish barbel. 



e. Air-bladder present; anal spines 2 Umbkixa, HOO. 



ee. Air-bladder none; anal spine single Menticikuus, ;501. 



U Lower jaw projecting beyond upper. 



/. l^nont short, blunt ; no canines; anal fin very smal ; soft pai"t of 



dorsal much longer than spinous part Larimus, ii02. 



tt, Vertebra} about 14 -f- 10 ; body elongate ; lower jaw projecting. (OtoUthiiKv.) 



li. Canine teeth none Atractosciox, 303. 



hh. Canines two (or one) in upper jaw only.. ..Cynosciox, 304. 

 ** Dorsals remote ; the second about as large as the anal. {Isoplsthincv.) 



t. Lower jaw projecting; anal siiines feeble; teeth small, 

 sharp, in narrow bands Seriphus, 305. 



294.— HAPLOIDOIVOTUS Rafinesque. 

 Fresh-water Drums.. 

 (Amhiodon Eafiuesque. ) 



{Aplodinoius Rafinesque, Joarn. de Phys. 1819, 418 : type Aplodinotus grunniens Raf.) 



Body oblong, the snout blunt, the back elevated and compressed. 

 Mouth rather small, low, horizontal, the lower jaw included. Teeth 

 in \ illiform bands, the outer scarcely enlarged. Xo barbels. Pseudo- 

 branchijB rather small; gill-rakers short and blunt. Lower i)haryn- 

 geals very large, fully united, with coarse, blunt, paved teeth. Preop- 

 ercle slightly serrate. Dorsal spines strong and high, with a close fit- 

 ting scaly sheath at base, the two dorsals somewhat connected. Second 

 anal spine very strong. Caudal double-truncate. Fresh waters of the 

 United States. (a-Aot-, a cloak; vwro?, back; according to Gill, from 

 the scaly base of the dorsal fin.) 



893. H. grunniens Raf. — Sheepshcad ; Thunder-pumper ; Drum; White Perch; 

 Croaker. 



Grayish silvery, dusky above, sometimes quite dark, the back some- 

 times with oblique dusky streaks along the rows of scales. Scales rather 

 thin, adherent, smaller on the back and belly. Second anal spine more 

 than half the leugth of the head. Snout very blunt, overlapping tlie 

 mouth. Eye large. Head 3^; depth nearly 3. D. IX-I, 30 ; A. 11, 7; 

 Lat. 1. 55. Great Lakes to Texas, abundant, reaching a weight of 50 to 



