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INDIANA UNIVERSITY STUDIES 



line joining tlieii* tips more arched and the hirgest point nearer the onter 

 than the inner margin ; each ramus of the lower jaw with seven to nine 

 regularly graduate teeth ; OA^erlapping and slightly asymmetric on the side 

 of the jaw. 



Gill-rakers about 4+7. minute, the tip of one not reaching the base of 

 the next. 



Scales large, thin, witli very few striae, regularly imbricate, without 

 interpolated scales ; caudal lobes with a few scales ; a series of scales in 

 part along the base of the anal in part on the sides ; lateral line complete, 

 decurved. 



Origin of dorsal midway between tip of snout and caudal ; highest 

 dorsal ray about one sixth the length ; adipose fin behind the vertical from 

 the base of the last anal ray; caudal lobes equal to the head; origin of 

 anal in front of vertical from last dorsal ray ; veutrals very short, not 

 reaching anal, their origin a little in advance of the origin of the dorsal ; 

 pectorals not reaching ventral s by two or more scales. 



A faint vertical humeral spot crossing the fifth and sixtli scales of the 

 lateral line; a silvery lateral band, sometimes ending in a caudal spot 

 extending, in part on the caudal ; fins all hyaline. 



This species differs from Deuterodon in the complete armature of the 

 cheeks, the presence of but four teeth in the inner series of the premaxil- 

 lary. It differs in the nature of its outer premaxillary teeth from the 

 typical Bryconamericus. 



Bryconamericus henni Eigenmann, sp. nov. 



Type, ^ 48 mm. 5410 a-d C. M., 13102 I. U. M. Paratypes over 40, largest 



53 mm. Yinces, Ecuador. Arthur Heun. 

 5411a-j C. M., 13124 I. T. M. Paratypes many, Colimes, Rio Daule, Ecuador, 



Arthur Henn. 



Very similar to Lanclonia laticeps. 



Allied to Argopleura in the ]>resence of a glandular structure on the 

 middle caudal rays ; differing from it in the absence of prominent lower 

 caudal fulcra; first ten. and hist ten developed rays of the anal of the male 

 with hooks. 



Head 4; depth 3-3.5; D. 10, A. 33; scales 8-38-5; eye 3 in head, 

 slightly greater than interorbital. 



Slender, compressed ; ventral surfaces rounded, predorsal surface with 

 a median series of scales ; snout pointed, mouth terminal, or superior ; 

 sliull rounded, parietal fontanel much longer and wider than the frontal ; 

 maxillary about .08 as long as eye, not nearly reaching suture between first 

 and second suborbital ; maxillary with a single, minute, hidden tooth, pre- 

 maxillary with three teeth in tlie front series and four in the back series ; 

 mandible with five graduate teeth ; a naked angle below the suture between 

 the first and second suborbitals ; gill rakers 12+11 all slender, the longest 

 about h?lf the length of the eye. 



Origin of dorsal equidistant from base of middle caudal rays iind 

 middle of eye. the fin pointed, less than length of head in height ; adipose 

 fin well developed; caudal lobes equal, about equal to length of head. 

 Anal falcate, the last ten rays in the male forming a second lobe; veutrals 



