36 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



Body little elongate ; the head rather broad, but not much depressed; 

 the anterior profile scarcely concave, elevated in front of dorsal fin ; 

 head somewhat broader than deep; interorbital space about If in head; 

 breadth of mouth If; length of snout 34' ; eye rather large, 5 to 7 in head, 

 placed close to the angle of the mouth, and not much about it ; vomerine 

 and palatine teeth confluent into a band, the component parts indicated 

 by conspicuous constrictions, more or less separated in the young; 

 vomerine patches considerably larger than those on the palatines, the 

 latter not prolonged backward. 



Maxillary barbels compressed, of varying length, longest in the young; 

 in the adult rarely reaching beyond the middle of the pectoral spine. 

 Mental barbels short, about 3 in head. Occipital process varying with 

 the sex — in the male broad-ovate, somewahat constricted toward the 

 base, nearly as broad as long, in the females more or less narrow, the 

 form and degree of roughness extremely variable ; the plates rough- 

 granular in old males, nearly smooth in the females, the occipital pro- 

 cess being more or less coarsely striate; cheeks little prominent; fon- 

 tanelle narrow, not very conspicuous, forming a groove which extends 

 from the interorbital space to the base of the occipital process. 



Dorsal spine slender and rather short, not produced into a filament, 

 the greatest height of the fin If in head, the anterior margin of the spine 

 weakly and bluntly serrated ; adipose fin short and high ; caudal widely 

 forked, the upper lobe little longest, slightly shorter than head ; anal 

 high anteriorly, emarginate, the anterior lobe much highest in the adult, 

 in which it extends considerably beyond the last rays of the fin. Pec- 

 toral spine slender, ending in a band-like filament, which usually reaches 

 about to the vent. Humeral process covered by soft skin. 



Color brownish above, with bluish and golden reflections, paler be- 

 low, the white of the lower parts almost everywhere soiled with dark 

 punctulations, which are especially numerous on the lower side of the 

 head. Dorsal dusky ; other fins pale, more or less soiled by dark points ; 

 the pectorals and veutrals more or less dusky above, but without dis- 

 tinct dark blotches; barbel dark : a pale spot in the center of the fon- 

 tanel le. 



This species is extremely common for the whole length of the Pacific 

 coast of tropical America. It reaches a length of about 20 inches, and 

 is known to the fishermen as "Bagre." It is rarely eaten. It was 

 observed by Mr. Gilbert at Mazatlan, Punta Arenas, Libertad, and 

 Panama. 



We are unable to find the type of this species in the Museum. 



SPECIMENS IN THE NATIONAL MUSEUM. 



28181. Mazatlan. Gilbert. 



28294. Mazatlan. Gilbert. 



29174 (5 specimens). Mazatlan. Gilbert. 



29310. Punta Arenas. Gilbert. 



2960G. Mazatlan. Gilbert. 



