178 



FISHES OF ILLINOIS 



ICTALURUS FURCATUS (Le Sueur) 

 (blue cat; chuckle-headed cat; fulton cat) 



Le Sueur, 1840, in Cuv. & Val., XV, 136 (Pimelodus). 



G., V, 103 (Amiurus); J. & G., 109; M. V., 39; J. & E., I, 134; N., 50; J., 66 (Ich- 



thaelurus furcatus, Amiurus nigricans [part]); F., 82 and 83, (furcatus, pondero- 



sus, nigricans [part] ); F. F., II. 7, 456; L., 9. 



Body slender, somewhat compressed, the back elevated, depth 4 to 

 4. 5 in length; profile long, steeper than in the next species, the elevation 

 18° to 23° and the contour broken at the nape (the elevation from that 

 point to dorsal being greater than from snout to nape) . Size large, reach- 

 ing a weight of over 40 pounds. Color bluish or slaty gray above, shading 

 to silvery below and almost white on belly; fins, especiallv the anal, fre- 

 quently edged with dusky ; spots very few or entirely absent. Head small, 

 wedge-shaped, more angular than in the next species, its length 4 to 4.4, 

 its greatest depth 5 . 2 to 5 . 6 in body; top of head and nape prominently 

 convex, the back subcarinate in front of dorsal, the skin thin and fitted 

 closely over the bones; mouth small, inferior, the lower jaw wholly 

 included; lips thin; maxillary barbels reaching past gill-opening; eye 

 small, oval, Iving on the median axis of the body and nearer lower than 

 upper surface of head; diameter of orbit 7.2 to 7.8 in head. Dorsal fin 

 high, nearer snout than adipose, its distance from snout 3 to 3.5 in 

 length ; the spine rather longer and more slender than in /. punctatus, its 

 length 1 . 5 to 1 . 7 in head ; the posterior edge usually furnished with well- 

 developed retrorse teeth. Caudal deeplv forked, the lobes about equal. 

 Anal fin long, of 30 to 35 rays, including rudiments, its base about ^ 

 length of body, the free margin straight or very slightly rounded. Pec- 

 toral spine a little shorter than that of dorsal; humeral process 1 . 3 to 1 . 6 

 in length of spine. 



Fig. 50 

 Anal and caudal fins of Ictaliirus furcatus. 



This species is found throughout the Mississippi Valley and the 

 Gulf states, being most abundant southward, and especially so in 

 the Atchafalaya in Louisiana, where one to two million pounds are 

 taken annually. It forms a large per cent, of the catch of catfishes 



