452 PROCEEDINGS OF THE ACADEMY OF [Oct., 



Subgenus GASTEROPELECUS Bloch. 



Upper anterior profile straight. 

 Gasteropelecus sternicla (Linnaeus). 



Head 3^; greatest depth If; D. ii, 8; A. in, 30 ; scales 30? (squamation 

 injured) in a lateral series from gill-opening above to base of caudal; 

 about 18 scales before dorsal; 13 scales in a transverse series between 

 origin of dorsal and that of anal ; 17? scales from gill-opening at origin of 

 pectoral to that of ventral; width of head about 2 in its length; 

 mandible 2^; snout 4^ in head measured from tip of upper jaw; eye 3|-; 

 interorbital space 2J. Length 2^^ inches, Surinam. Bonaparte 

 Coll. (No. 456.) Dr. T. B. Wilson. 



THORACOCHARAX subgen. nov. 

 Type Gasteropelecus stellatus Ivner. 



Anterior profile of back convex. 

 {ddjpa^^ cuirass; /«/>«^, Charax.) 

 Gasteropelecus stellatus Kner. 



Cope, Proc. Amer. Philos. Soc. Phila., XI, 1869-70 (August 19, 1870), p. 



566. Pebas, Eastern Peru. John Hauxwell. Cope, Proc. Acad. 



Nat. Sci. Phila., 1871 (1872), p. 265. Ambpacu Pdver. John Haux- 

 well. 



Head 3| to 3f ; depth If to 1|; D. ii, 12 to ii, 15, usually ii, 13; A. 

 Ill, 35 to III, 39; scales (squamation damaged) 18? to 20 in a lateral 

 series from gill-opening to base of caudal; pectoral (damaged) about 

 If to 2 in head and trunk; eye 3 in head, measured from tip of upper 

 jaw; interorbital space 2 to 2f ; total length of 7 fish IfV to 3|- inches. 

 Pebas, eastern Peru, and the Ambyiacu River. John Hauxwell. 



CHARACIN^. 

 Asiphonichtliys sternopterus Cope. 



Amer. Nat., XXVIII, 1894, p. 67. T>T)e, No. 21,-559, A. N. S. P. Upper 

 waters of the Jacuhy River, in the Brazilian State of Rio Grande do Sid. 



H. H. Smith. Cope, Proc. Amer. Philos. Soc. Phila., XXXIII, 1894 



(January 5), p. 85, PI. 5, fig. 2. Type. 



Width of head 2\ in its length ; interorbital space 3|-. Body strongly 

 compressed, edges rather rounded. Postdorsal region a little broad 

 and preventral quite so. Postventral region well compressed. Head 

 well compressed. Snout broader than long, and siu-face convex. 

 Mouth broad. Mandible with rami not elevated inside of mouth. 

 Teeth in jaws small, irregularly biserial in upper, and with several 

 short canines. Mandibular teeth in front of jaw a little enlarged and 

 with at least 4 more or less developed canines. Maxillary with a 

 series of fine teeth along most of its edge. Interorbital space a little 



