CATFISH GENUS NOTURUS RAFINESQUE 89 



nasal pores. The ventral surface of the head, except the lower lip, and 

 the abdomen, except a narrow band just anterior to the pelvic fins, 

 are usually unpigmented. The vertical fins of many specimens have a 

 black margin. 



It is distinguished from Noturus exilis, with which it has been asso- 

 ciated, by the longer caudal fin, the included lower jaw, and the greater 

 number of preoperculomandibular and nasal pores; from Noturus 

 nocturnus, an apparent close relative, by the more depressed skull, 

 better developed pectoral spine serrae, and usually 38 or more verte- 

 brae; and from Noturus funebris and A^. phaeus by a shorter anal fin 

 and a poorly pigmented ventral surface. 



Description. — Other counts and measurements are given in tables 

 17 to 26. Body elongate; caudal peduncle deep, both anteriorly and 

 posteriori}', deeper than head depth; head depressed; lower jaw in- 

 cluded; premaxillary tooth band usually obtusely angulate at corners; 

 dorsal spine moderate in length, stiff; pectoral spine long, slightly 

 curved, without anterior serrae, but with numerous distinct posterior 

 serrae, which may become irregularly fused in old specimens; humeral 

 process about equal in length to the diameter of the pectoral spine; 

 adipose fin broadly united to the moderately high procurrent caudal 

 fin; caudal fin truncate or rounded behind; eye moderate, 1.9 to 2.6 

 times in snout; gill rakers six to ten on first arch; size fairly large. 

 Specimens over 100 mm. are frequently obtained; one of the largest 

 is a Virginia specimen 126 mm. in standard length. 



The caudal fin has (extremes in parentheses): (21) 23 to 26 (28), 

 mean 24.3, upper simple rays; (15) 17 to 20 (22), mean 18.4, branched 

 rays, of which there are nearly always 7 in the upper-half of the fin 

 and most frequently 10 to 13 in the lower-half; (13) 16 to 20 (23), 

 mean 18.3, lower simple rays. The soft dorsal rays are five (in 3), 

 six (119), and seven (2). The posterior edge of the pectoral spine is 

 serrated, with up to nine serrae. 



In cleared and stained specimens for North Carolina, Virginia, 

 and New York: vertebrae anterior to the anal fin origin 12 (11), 

 13 (23), 14 (2). In 82 of the 92 sides of the pectoral arches examined, 

 the ossified radials are tightly fused; the other sides show partial 

 fusion of the elements, perhaps because relatively small specimens 

 were used. The hypurals are separate in 39 specimens; hypurals 2 

 and 3 fused (in 4), hypurals 4-5 fused (1), and hypurals 6-7 fused (3). 



General color yellowish to slate-gray, lighter on ventral surfaces. 

 Top and sides of body and head uniformly darkly pigmented; no 

 blotches or light areas present; barbels usually with some chromato- 

 phores, those above dark, the barbels below light colored; chin in 

 front of the mental barbels pigmented, and a narrow bridge of pig- 

 ment crosses abdomen in front of pelvic fins; otherwise, abdomen and 



