THE SHORE FISHES OF PERU 127 



flat interorbital, which rises scarcely more than diameter of pupil 

 above upper margin of eye; and the broad mouth, which is arched 

 forward only slightly. 



Range. — Panama Bay to Peru. 



Genus ARIUS ^ Cuvier and Valenciennes, 1840 



Arius may be recognized by the absence of teeth on the vomer and 

 by the rather broad patches of moderately blunt teeth on the palatines, 

 which do not have backward projections. 



A single species, characterized by its numerous anal rays, comes 

 within the scope of the present work. 



ARIUS MULTIRADIATUS Giinther 



Bagre 



Figure 28 



Arius multiradiatus Gcnther, 1864, p. 173 (brief diagnosis, after Kner and 



Steindachner) . — Meek and Hildebrand, 1923, p. 123, Panama Bay 



(synonymy; description). 

 Bagrus arioides Kner and Steindachner (not of Cuvier and Valenciennes) 



1865, p. 47, Rfo Bajano, Pacific slope of Panama (indicated as new with an 



interrogation point and without showing that B. arioides is of Cuvier and 



Valenciennes, 1839, p. 440; description). 

 Tachysurus equatorialis Starks, 1906, p. 766, figs. 3, 4, Guayaquil, Ecuador 



(original description). — Evermann and Radcliffe, 1917, p. 32, Paita, 



Peru (description). 

 Tachysurus jurthii Fowler, 1941a, p. 370 (references; only those pertaining to 



T. equatorialis are certainly this species). 



Head 3.5 to 3.75; depth 4.7 to 5.2; D. I, 7; A. 25 to 27; P. I. 10. 



Body notably deeper than broad at origin of dorsal, tapering 

 moderately posteriorly; caudal peduncle strongly compressed, its 

 depth 2.8 to 3.3 in head; head moderately broad, its greatest width 

 about equal to its length less half the snout; interorbital space 2.0 to 

 2.8 in head; snout broadly rounded, 2.75 to 2.9; eye lateral, 5.0 to 

 6.2; mouth arched forward broadly, its width at angles 2.6 to 2.9; 

 teeth in jaws pointed, in moderately broad bands; palatine teeth 

 rather blunt, in a short band, tapering but not pointed posteriorly; 

 gill rakers scarcely longer than pupil, 5 or 6 on upper and 13 or 14 on 

 lower limb of first arch; upper surface of head rather rough, without 

 distinct ridges; fontanel failing to reach occipital process by about 

 half diameter of eye, extending forward somewhat beyond posterior 

 rim of orbit, closed between eye, and reappearing as an elongate pit 

 on snout; occipital plate anteriorly broad, its width somewhat exceed- 



• I am using Arius with the knowledge that several authors have considered Tachysurus, which is an older 

 name, as available. However, as Tachysurus sinensis, the type of the genus, was based on a painting of a 

 flsh from fresh water of China, it seems highly improbable that it is the same as Arius as herein defined. 

 Furthermore, modem classification of the catfishes is based in large part on the character of the teeth, which 

 of course could not be determined from a painting of the exterior. For a rather detailed discussion of this 

 matter see Regan (1907, p. 125, footnote). 



