264 



THE AMERICAN CHARACIDAE. 



Specimens examined. 



Catalogue 

 number 



4919 C, 12757 I. 



4920 C, 12756 I. 

 5390 C, 13083 I. 

 5388 C, 13081 I. 

 6695 C, 13581 I. 

 34589 U. 



Number of 

 specimens 



55 

 40 



6 



1 



QO 



3 



Size 

 in mm. 



140' 



100 1 



47, 56, 67 1 



Locality 

 Boca de Certegui 

 Quibdo 

 Certegui 

 Quibdo 

 Truando 

 Para 



Collector 

 Eigenmann 

 Eigenmann 

 Wilson 

 Wilson 

 Wilson 

 J. C. Brevoort 



Astyanax stilbe, A. caucanus, and A. atratoensis are certainly closely related 

 if not synonymous. 



The following description is based on three specimens 34589 U. S. N. M. 

 from the type-locality. The two larger specimens are more elongate but other- 

 wise very similar to the smaller. In the following description the statements 

 in brackets refer to the smaller specimen only. 



Head about 3.75 (3.6); depth 2.66 (2.4); D. 11; A. 40 (36); scales 8-40-7 

 (8_40_8 to ventrals) ; eye 2.6-2.66 in the head, 2 in the head less opercle, a Uttle 

 longer than interorbital. 



Compressed, profiles symmetrically curved. Predorsal and pre ventral 

 areas bluntly keeled, the mid-hne of the former naked to near the dorsal, a few 

 median scales near the dorsal, otherwise the scales of the two sides approaching 

 and sometimes overlapping the middle Une. 



Occipital process about 3 in the distance to the dorsal. Fontanels large, 

 the frontal about 1.33 in the parietal without the groove. Second suborbital 

 leaving a distinct naked border which is a little naiTower below. Maxillary- 

 premaxillary border equals the eye. Four teeth in the outer series of the pre- 

 maxillary, five in the inner. Maxillary with one tooth. Mandible with five 

 graduated teeth, the last one qviite small, and about 5 minute subcorneal teeth. 

 Denticles of the second series of premaxillary teeth in a crescent. 



Gill-rakers 10 + 17. 



Origin of dorsal nearer snout than caudal ; margin of dorsal obliquely trun- 

 cate, its highest ray about equal to the length of the head. Origin of anal on 

 or a httle behind the vertical from the last dorsal ray. Ventrals reaching 

 anal in the two larger. Pectorals reaching three or four scales beyond origin 

 of ventrals. 



Scales regularly imbricate except over the anal where the rows are deflected 



' To base of caudal. 



