34 MEMOIRS OF THE CARNEGIE MUSEUM. 



opercle in front and behind; a single postorbital, its lower half in contact with 

 the vertical limb of the preopercle, a naked margin behind its upper half; no tubes 

 on the suborbital or postorbital; mouth large, very oblique, the chin entering the 

 profile; the maxillary-premaxillary border a gentle curve, longer than eye; maxillary 

 reaching beyond suture between second and third suborbital; maxillary 

 with thirteen conical teeth along practically its entire margin; premaxillary with 

 six slightly graduate teeth with a small notch on each side near the tip of each 

 tooth; mandible with twelve graduate teeth along the greater part of its margin, 

 similar to those of the premaxillary, the lateral ones simply conic. Gill-rakers 

 4 + 7. 



Origin of dorsal equidistant from tip of snout and near end of middle 

 caudal rays; the highest ray a little shorter than head; origin of anal under 

 anterior part of dorsal; ventrals not quite reaching anal, pectorals a little beyond 

 origin of ventrals. 



Each scale with two sub-parallel radial striae dividing the scale into three 

 fields of about equal height; caudal naked; pores on but few scales. 



A sub-triangular caudal spot, its base across the entire caudal peduncle, its 

 tip on the basal third of the middle caudal rays; dorsal nearly evenly peppered; 

 sides of head and abdomen silvery; chin, upper lip, and sides peppered, the pepper- 

 ing densest along the back and along the base of the anal, the spots becoming larger 

 along the base of the anterior anal rays, and continued forward to the ventrals; 

 a dark band beginning at the base of the first to fourth anal rays, extends 

 obliquely to the tip of the sixth and along the margin of the succeeding rays; 

 middle caudal rays without chromatophores, the lobes faintly peppered. 



12. Aphyocharax nattereri Steindachner. 

 Tetragono'pterus diaphanus Cope (part), Proc. Am. Philos. Soc, Vol. XVII, 1878, 



p. 691 (Peruvian Amazon). 

 Cheirodon pidcher Steindachner, Flussf. Slidam., Vol. IV, 1882, p. 39 (Villa Bella); 



Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., Vol. XIV, 1891, p. 54; 



Fowler, Proc. Acad. Nat. Sci. Phila., 1906, p. 332, fig. 21 (based on Cope's 



specimens mentioned above). 

 Cheirodon nattereri Steindachner, Anz. Akad. Wiss., Wien, 1882, p. 180 (Villa 



Bella); Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., Vol. XIV, 1891, 



p. 54; Ulrey (part), Ann. N. Y. Acad. Sci., Vol. VIII, 1895, p. 291 (Para); 



?Boulenger, Boll. Mus. Univ. Torino, Vol. XIV, 1900 (Urucum, Matto 



Grosso); Eigenmann, Reports Princeton Univ. Exped. Patagonia, Vol. Ill, 



1910, p. 429. 



