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INDIANA UNIVERSITY STUDIES 



Gill-rakers 8 + 9. 



Origiu of dorsal equidistant from tip of snout and end of lateral line 

 or nearer the snout, its margin subtruncate, its highest ray extending for 

 a distance equal to about Uyo scales beyond the tips of the penultimate, 

 about equal to the length of the head, caudal lobes about 3.5-4 in the 

 length ; anal slightly emarginate, its origin under the middle of the 

 dorsal or a little further forward; ventrals not reaching anal, their origin 

 equidistant from tip of snout and last fourth of the anal; pectorals reach- 

 ing origin of ventrals or a little beyond. 



Scales thin, with about 10 radii, regularly imbricate, except over the 

 anal where there are a few interpolated scales ; lateral line much more 

 sagging than in B. tolhiiw; caudal naked, the lobes with a basal sheath ; 

 anal with a variously developed sheath of a single series of scales ; 

 axillary scale short. 



Middle caudal rays black ; a large, faint shoulder band crossing the 

 third to fifth scale of the lateral line. Silvery. 



A specimen from Peiias Blancas, 42 mm. CM. No. 5056 has depth 

 3.()S ; A. 2.9 ; scales 7, .5-41 -5. 



15. Bryconamericus decurrens sp. nov. 



Type 57 mm. to base of caudal. Soplaviento. CM. No. 5055. 

 Paratype. 53 nun. to base of caudal. I.U.M. No. 12829. 

 Evidently closely allied to B. (Jcittatiis, from which it differs much in 

 shape. 



Head 4.33; depth 3; D. 10; A. 31; scales 9-44-6; eye 3 in the head, 

 equal to the interorbital ; depth of caudal peduncle equal to its length ; 

 premaxillary with four or five teeth in the outer series, four in the inner ; 

 six teeth on the maxillary on half or a little less than half the margin 

 of the maxillary. The last tooth in the paratype is remote from the rest, 

 mandibular y teeth of the sides abruptly smaller. 



Origin of dorsal equidistant from tip of snout and end of lateral 

 line ; origin of anal under anterior half of dorsal, its base 2.8-3 in the 

 length ; interpolated rows of scales beginning over the middle of the 

 ventrals, the rows of scales distinctly decurvent to the anal. Otherwise 

 as in dentatus. 



16. Bryconamericus or Hemibrycon boquiaB spec, rov ? 



Tyi:>e, 48 mm. to base of caudal. Boquia. CM. No. 5059 a. 



Paratypes, 21. Boquia. CM. No. 5059 b-k ; I.U.M. No. 12831. 



These specimens are in very bad condition. They belong to a species 

 evidently closely related to if not identical with toUmw. They differ in 

 having the anal rays ranging from 26-29 ; the mandibulary teeth are quite 

 different, the first three teeth are comparatively large and nearly uniform 

 in size, the fourth is notably smaller and the rest are suddenly minute. 



These specimens came out of the brook at Boquia and there will be 

 no difiiculty in determining their relationship if additional specimens are 

 taken at the same place. They were associated with the similar Brycon- 

 americus caucanus. 



