EIGENMANN : NEW FISHES FROM WESTERN COLOMBIA 



3 



long, entirely covered by the second suborbital ; the mouth very small, the 

 maxillary not reaching to the eye ; lo^^-er jaw with nine t(!eth on each side, 

 premaxillary with six, maxillary with eight, the first four tricuspid, the 

 last four conical. The first four forming a continuous series with those of 

 the premaxillary the four conical ones on the distal, curved portion of tlie 

 bone. Gill rakers about 5+S. 



Scales thin, the margins obscure, a single row of scales along the base 

 of the anal rays ; a few scales along the base of the caudal lobes. 



Origin of dorsal slightly behind the middle of body ; height of dorsal 

 equals length of head ; caudal lobes about equal to the height of the 

 dorsal; origin of anal about equidistant froan the snout and origin of its 

 last third ; ventrals small, reaching the anal ; pectorals equal to the head 

 less snout, reaching to middle of ventrals. 



Translucent, a median dusky band along middle of caudal peduncle, 

 fading out forward and continued narrowly on middle caudal rays ; scales 

 of back faintly marked with chroma tophores, which become restricted to 

 the margin of the scales on the upper part of the back. Chin and maxillary 

 black, sometimes a dark streak back from upper part of gill opening. 



MICROBRYCON Eigenmann and Wilson, gen. nov. 



^^ery similar to Gephyrocharax, the lateral line incomplete and the 

 anal much shorter. 



Microbrycon minutus Eigenmann and Wilson, sp. nov. 



5422 C. M. Type, 24 mm, 13109 I. U. M. Paratype 24 mm. Truando. Wilson. 



Head about 3.66 ; depth 3.5; D. 10; A. 18; scales about 32; eye 

 equals interorbital, 2.5 in head. 



Skull broad, the fontanels linear, expanding into a rhomboid :it the last 

 occiptal process ; second suborbital narrow, covering the entire cheek ; 

 mouth large, oblique; maxillary two thirds as lorg as eye, with one tooth; 

 prem,axillar with four teeth in the outer series, five in the inner ; lower 

 jaw with about eleven teeth on the sides, most of which are minute, 

 conical ; four larger teeth in front, of which the first and third are the 

 largest. 



Origin of dorsal about one and a half times as far from the snout as 

 from the caudal ; its highest ray shorter, the caudal lobes longer than the 

 head ; adipose well developed ; anal comparatively short, its origin but 

 little in front of the vertical from the front of the dorsal; ventrals reach- 

 ing or not quite reaching origin of anal, pectorals to posterior third of 

 ventrals ; anal emarginate, its last ray considerably produced. 



Scales thin without apparent lines. Caudal and anal naked. 



A black line along the sides; a large spot at base of caudal; a few 

 chromatophores along base of anal; back with scattered chromatophores. 

 without black median line. 



CERATOBRANCHIA Eigenmann, gen. nov. 

 A Tetragonopterid in which the outer series of teeth of the in-enmx- 

 illary has become the dominant one, 



