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INDIANA UNIVERSITY 



to the tips of the middle caudal rays. Scale margins above lateral stripe 

 outlined with dusky, below heavily sprinkled with chromatophores. Base& 

 of caudal lobes in life evidently tinged with deep red. 



Bryconamericus novae Eigenmann and Henn, sp. nov. 

 Type, 56 mm., 3568a CM.; paratypes 9, 30-57 mm. 

 3568b-j C. M. 3, 40-50 mm., 13308 I. U. M. 



Below Cachoeira da Velha near Piabana, Rio Novo of Rio Tocantins, 

 Lower Amazon basin. Coll., J. D. Haseman. 



Allied to B. hijphessus differing in being less elongate, having the dorsal 

 profile more arched and having an additional row of scales below the lateral 

 line. Possibly identical with B. diaphanus (Cope). 



Head 4; depth 3.2-3.6; D. 10; A. 18-20; scales 4-36-3; eye 2.4, a little 

 greater than the interorbital. 



Gill rakers 6+5, those of the upper limb minute. 



Slender, compressed, dorsal and ventral profiles equally but only slightly 

 arched; preventral area rounded without a regular median series of scales; 

 postanal area rounded with 6 median scales; predorsal area with a median 

 series of about 10 scales. 



Occipital process short, about one-seventh of the distance from its base 

 to the dorsal, bordered by two scales on the sides; interorbital flattened or 

 slightly convex; frontal fontanel triangular, as wide as the parietal and two- 

 thirds as long as the parietal without the occipital groove. 



Snout blunt, lower jaw not extending beyond upper; maxillary slender, 

 extending to suture between first and second suborbitals, its length four-fifths 

 that of the eye; cheeks not very wide, covered by the expanded second subor- 

 bital, the anterior angle of which is overlapped by the first suborbital. 



Maxillary with two or three minute tricuspid teeth in the inner angle 

 near its symphysis with the premaxillary. Three to six conically tricuspid 

 teeth in the first row or outer series of the premaxillary, the second or tooth 

 next the symphysial tooth and the fourth are set back. These teeth are variable 

 in number; there may be four on one ramus and five on the other or as in the 

 type, six on the right ramus and three on the left. Inner series of premaxillary 

 of four three or four-pointed teeth. Mandible with four large five-pointed 

 teeth and a variable number of small tricuspids on the sides. 



Scales cycloid, regularly imbricate, without interpolated or omitted 

 scales; anal sheath of a single row of bifid scales on the base. Fourth lateral 

 series or series above lateral line horizontal, of large scales, their vertical 

 height about three-fourths that of eye. Lateral line decurved, parallel with 

 the row of scales below it. 



Dorsal origin about equidistant from tip of snout and base of middle 

 caudal rays, height of its longest ray about 4.5 in the length; anal origin 

 one scale behind vertical from last dorsal ray and equidistant from base of 

 pectoral and base of caudal. Ventrals shorter than the pectorals, not reaching 

 the anal. Pectorals barely reach ventrals, their length equal to the head 

 minus the snout. 



Straw colored, top of head darker but without a predorsal line; a broad 

 postdorsal color band to caudal base. Cheeks and operculum bright silvery; a 

 broad horizontal silvery lateral stripe just above the lateral line, terminating 

 in a dusky caudal stripe or spot on caudal peduncle and base. A faint vertically 

 elongate humeral spot imder the third and fourth scales of the lateral line. 



