INVESTIGATIONS IN MISSISSIPPI, LOUISIANA, AND TEXAS. 305 



f :8. Ictalurus furcatus (LeSueur). "Blue Cat"; " Poisson Bleu." 



This is by far the most important of all the catfishes of the region covered 

 by this report. It attains a weight of 100 pounds, and the importance of 

 the species is shown in the earlier portions of this paper. Its abundance, 

 distribution, and habits have already been fully discussed. Until these 

 investigations were made the large catfish of the Lower Mississippi Valley 

 had been identified by most ichthyologists as the Gadus lacustris of Walbaum. 

 Pimelodus nigricans LeSueur and Amiurus ponderosus Bean were thought to 

 belong to the same species as Walbaum's Gadus lacustris, and the species 

 stood as Ameiurus lacustris (Walbaum). The type of Gadus lacustris came 

 from Arctic America, and we have no certain means of knowing whether it 

 was an Ameiurus or an Ictalurus. LeSueur'e 'Pimelodus nigricans came from 

 Lakes Erie and Ontario, and was probably an Ameiurus, though a reexam- 

 ination of specimens from those lakes must be made before we can feci certain 

 that such is the case. An examination of the skeleton of the type of Amiurus 

 ponderosus, which is preserved in the U. S. National Museum, shows that it 

 belongs to the genus Ictalurus, as is evidenced by the notched supraoccipital 

 which forms a continuous bony ridge with the first interspinal of the dorsal. 

 LeSueur's Pimelodus furcatus came from New Orleans and was unquestionably 

 the same as the blue cat of the Atchafalaya River. At least until the large 

 catfish of the Great Lakes can be carefully studied, the blue cat of the Lower 

 Mississippi Valley must stand as Ictalurus furcatus, and Amiurus ponderosus 

 goes in its synonymy. 



The number of anal rays in numerous specimens counted varies from 

 31 to 33. A spent female, 30 inches long and weighing 17 pounds, gave the 

 following measurements : Head4; depth 4.34; D.i,6; P.i,9;A.32; distance 

 from tip of snout to origin of dorsal fin 2.64 in body ; greatest width of head 

 1.34 in its length; interorbital width 2; width of mouth equals interorhital 

 width; maxillary barbel not reaching beyond head; humeral process about 

 3 in pectoral spine ; anal base nearly £ longer than head. Barbels usually 

 color of fish, rarely black. In other respects the description of Ameiurus 

 lacustris in Jordan & Evermann's Fishes of North and Middle America agreed 

 perfectly with this specimen. The color of this species, as found in the 

 Atchafalaya River, is a dull or olivaceous blue, pale or whitish below, with- 

 out spots anywhere. 

 9. Ictalurus anguilla Evermann & Kendall. "Eel Cat"; " Willow Cat." 



The following is the original description of this species: Head 4; depth 

 4.5; eye 7 in head; snout 2.8; maxillary (without barbel) 3; free portion of 

 maxillary barbel longer than head ; dorsal spine 2 in head ; pectoral spine 2 ; 

 width of mouth 2. D. I, 6; A. 24; vertebrae 42. Head large, broad, and 

 heavy; mouth unusually broad; cheeks and postocular portion of top of 

 head very prominent ; interorbital space flat, a broad, deep groove extend- 

 ing backward to origin of dorsal fin; body stout, compressed posteriorly; 

 back scarcely elevated. Eye small; maxillary barbel long, reaching con- 

 siderably past gill-opening; other barbels short. Origin of dorsal fin equi- 

 distant between snout and origin of adipose fin, its distance from snout 2.6 

 in length of body; base of dorsal fin 3.5 in head; longest dorsal ray 1.75 in 

 head ; dorsal spine strong, entire both before and behind ; pectoral spine 

 strong, entire in front, a series of strong retrorse serrae behind; humeral 

 process 2.2 in pectoral spine; ventrals barely reaching origin of anal, their 

 length 2 in head; anal fin long and low, the longest rays about 2.2 in head; 

 base of fin greater than head, 3.2 in body ; caudal moderately forked, the 

 middle rays about 2.2 in outer rays, which are about 1.4 in head. 



Color, uniform pale-yellowish or olivaceous; no spots anywhere. 



A comparison of the skull with that of I. furcatus and /. punctatus of the 

 same size shows a number of very marked differences. Nearly all the bones 

 F. R. 98 20 



