CATFISH GENUS NOTURUS RAFINESQUE 147 



bar, and the creamy white area on the upper procurrent caudal 

 rays. 



In A^. albaier there are 45 to 54 caudal rays, usually 9 pelvic rays, 

 normally 2 internasal and 11 preoperculomandibular pores, and 13 

 to 16 anal rays. The posterior process of the clei thrum is very short 

 or obscure and the anterior serrae of the pectoral spine are nearly 

 obscure. 



Description. — Other counts and measurements are given in tables 

 17 to 26. Body rather elongate for a Rabida, the greatest depth under 

 the dorsal fin; caudal peduncle slightly tapering posteriorly, as deep 

 as the head back of the eyes; eye 1.5 to 2.4 times in snout; head 

 rounded or somewhat flattened above, little depressed; snout slightly 

 depressed; lower jaw included; premaxillary tooth band with poste- 

 rior corners rounded or obtusely angulate; pectoral spine (pi. 4, 

 fig. 4) relatively short, rather slender, and nearly straight, with the 

 anterior serrae weak or almost obscure; serrae of the posterior edge 

 rather numerous and with tips curved toward spine base (except 1 

 to 3 proximal serrae); humeral process blunt, poorly developed or 

 nearly obscure, seldom as long as the width of the shaft of the pectoral 

 spine; dorsal spine moderately slender; adipose fin high, with a 

 rounded upper edge, no free posterior flap, and united to the moder- 

 ately long procurrent caudal rays; posterior end of caudal fin rounded 

 or truncate; gill rakers six to eight on the first arch. 



In 91 specimens, 90 have 6 soft dorsal rays, 1 has 5. In 87 specimens 

 (extremes in parentheses): upper simple caudal rays (15) 17 to 19 

 (21), mean 18.02; branched caudal T&ys (one aberrant count of 12), 

 otherwise (15) 16 (17), mean 15.9, of which 7 are usually in the upper 

 part of the fin and 9 in the lower half; lower simple caudal rays (13) 

 14 to 17 (18), mean 15.5. There are three to eleven posterior serrae of 

 the pectoral spine. The largest specimen measures 89 mm. in standard 

 length; most are under 60 mm. 



In a stained specimen the ossified pectoral radials are tightly fused 

 on each side and there are 13 vertebrae anterior to the origin of the 

 anal fin. 



Body color yellowish with prominent black or brown blotches. In 

 preservation, yellowish or brown with contrasting dark brown or 

 black markings; top of head dark brown with a posterior bar that 

 extends to the branchiostegal membrane and onto the operculum; 

 a dark band extends from the snout around the eye, backward to 

 meet the first, outlining a light postorbital spot; anterior nares 

 pale, but usually with some pigment; upper barbels pigmented; 

 lips pale, with some pigment in front of and occasionally on mental 

 barbels; a light band (not prominent) of pigment anterior to pelvics; 

 remainder of lower head, abdomen, and pelvic fins immaculate; anal 



