2, PROCEEDINGS OF THE NATIONAL MUSEUM vol.82 



c'. Dorsal spines rather slender and weak, abruptly graduated 

 to the long middle spines, behind which the margin of the 

 fin is nearly straight. Anterior interneurals not greatly 

 strengthened, with low and blunt lateral ridges. Pec- 

 toral fin longer, with upper edge nearly straight to tip, 

 and lower rays only slightly frayed and silky. Fins pale, 

 with or without black markings, 

 d*. Lower jaw very strong, projecting forward at the sym- 

 physis beyond the upper, so that the teeth of the two 

 jaws are far from being opposed. Body more nearly 

 oblong (depth about two-fifths standard length). Anal 

 fin relatively short, with fewer than 25 soft rays, 

 e*. Gill rakers long and numerous (about 20 below angle). 

 Mouth strongly oblique. Vertebrae 32 (15 + 17), of 

 which only 11 support anal base. Dorsal and ven- 

 tral contours about equally curved. Body rather 

 strongly compressed. 

 f. Eye little enlarged (about one-fifth length of head). 

 Anterior ventral edge not sharpened or strongly 

 curved. Color : Sides not barred ; pelvic fins 



plain; anal with a black blotch Hypocritichtliys analis 



d^ Lower jaw less prominent; the teeth of the two jaws 

 nearly opposed. Body more rounded and deeper 

 (depth about half standard length). Anal fin longer, 

 with more than 28 soft rays. 

 e^ Gill rakers relatively long and numerous (more than 

 15 below angle). Mouth excessively oblique. Ver- 

 tebrae 33 to 35, of which 12 to 14 support the anal 

 base. Dorsal contour somewhat less strongly curved 

 than the ventral. Body very strongly compressed. 

 f. Eye excessively enlarged (about two-fifths length of 

 head). Gill rakers longer, and more than 20 below 

 angle of first arch. Anterior ventral edge blunter 

 and less strongly curved. Color : Sides occasion- 

 ally faintly barred; pelvic fins black distally; anal 



without black edge or blotch Hyperprosopon argenteum 



f. Eye moderately enlarged (about one-third length of 

 head). Gill rakers shorter; fewer than 20 below 

 angle of first arch. Anterior ventral edge rather 

 sharp and very strongly and evenly curved. Color : 

 Sides rather faintly barred ; pelvic fins plain ; anal 



fin with an inky-black margin Tocichthys ellipticus * 



e*. Gill rakers relatively short, thick and few (only 11 to 



13 below angle). Mouth only moderately oblique. 



Vertebrae 82 (14 + 18), of which only 11 support 



the anal base. Dorsal and ventral contours about 



equally curved. Body less strongly compressed. 



f*. Eye smaller. Anterior ventral edge blunt and not 



very strongly curved. Color : Sides rather strongly 



barred ; fins without black markings, but reddish 



(especially the caudal) Holconotus rhodoterus 



^ This is the species previously called Hyperprosopon agassizii. On its nomenclature, 

 see Hubbs (1918 and 1928). The supposed difference in dentition, pointed out in the 

 original diagnosis of Tocichthys, does not hold well. 



