116 Bulletin 47, United States National Museum. 



i. Supraoccipital bone continued backward from the nape, its notched 

 tip receiving the bone at base of dorsal spine, so that a contin- 

 uous bony bridge is formed under the skill from snout to l>as<- 

 of dorsal; caudal fin forked. ICTALUHUS, 7(5. 



it. Supraoccipital not reaching interspinal bones, the bony brid^v 

 more or less incomplete. AMEIURUS, 77. 



gg. Premaxillary band of teeth with a lateral backward extension on eacli 

 side; lower jaw projecting; dorsal spine weak. LEPTOPS, 78. 



ff. Adipose fin keel-like, adnate to the back. 



j. Baud of teeth in upper jaw with a backward extension at its outer posterior 

 angle, as in Leptops. NOTURUS, 79. 



jj. Band of teeth in upper jaw without backward extension, as in Ameiurus. 



SCUILBEODES, 80. 

 PIMELODIN;E: 

 ee. Posterior nostril without barbel; barbels G; adipose fin well developed; teeth in 



villiform bands. 

 k. Teeth on vomer none, or in small patches. 



i. Head covered with soft skin above, not granulated. Snout broad, scarcely 

 produced; barbels terete or slighlty flattened, not margined; head longer 

 than broad. 



m. Occipital process, if present, not reaching the .dorsal plate; dorsal 

 spine pungent. RHAMDIA, 81. 



mm. Occipital process narrow, reaching the dorsal plate; fontanelle reach- 

 ing base of occipital process, a bridge across it above posterior 

 margin of eye; humeral process spine-like. PIMELODELLA, 82. 

 ZZ. Head granulated above, naked or partially naked ; occipital process usually 

 reaching dorsal plate; fontanelle not continued behind eyes; adipose 

 fin longer than high; humeral process broad; not spine-like. 



PIMELODUS, 83. 



68. FELICHTHYS, Swainson. 

 ( GAFF-TOPSAIL CATFISHES.) 



Breviceps, SWAINSON, Nat. Hist. Fishes, 1, 328, 1838, (bagre), name preoccupied. 



Felichthys, SWAINSON, 1. c., n, 305, 1839, substitute for Breviceps, (bagre). 



Ailurichthys, BAIRD & GIRARD, Proc. Ac. Nat. Sci. Phila., 1854, 26, (marinm). 



JElurichthys, GILL, corrected spelling. 



Mystus, GRONOW, Cat. Fishes, Ed. Gray, 165, 1854, (carolinensis), name preoccupied. 



PtmeJodus,'BLEEKER, Silures de Suriname, 65. 1864, (bagre), not of Lacepede, as restricted by Gill. 



Body rather elongate, little compressed. Head depressed, broad above. 

 Mouth large, the upper jaw the longer. Teeth all villiform; those on the 

 vomer and palatines forming a more or less perfectly crescent-shaped band. 

 Barbels 4; maxillary barbels band-like, very long; chin with 2 short 

 barbels. Nostrils close together, the posterior with a valve ; nuchal region 

 with a granulated, bony buckler. Fontauelle large, well forward. Dor- 

 sal fin short, in front of the ventrals, with 1 sharp spine and Trays. Pec- 

 torals with a similar spine ; pectoral spines, and sometimes dorsal spine 

 also, ending in a long, striated, band-like filament. Adipose fin moderate, 

 free behind. Caudal fin widely forked; anal moderate, emarginate; ven- 

 tral rays 6. Gill membranes somewhat connected. Tropical waters of 

 America, the species all marine, (fells, cat; t0wf, fish.) 



a. Dorsal spine not produced in a long filament; occipital process large, shaped like a clover 

 leaflet; gill rakers 5 + 14; base of ventrals about equidistant from snout and caudal. 



PANAMENSIS, 156. 



