334 Bulletin 47, United States National Museum. 



blackish caudal spot. (Giinther.) Oaxaca, Mexico, and Rio Chagres, 

 south to Brazil, (as ne us, brassy.) 



Tetragonopterus leneus, GUNTHER, Proc. Zool. Soc. Lond., 1860, 319, Oaxaca, Mexico. (Coll. 

 Salle.) GUNTHER, Cat., v, 326, 1864. 



554. TETRAGONOPTERUS RTJTILUS, Jenyns. 



Head 4i; depth 2|; eye 3i in head. D. 11 ; A. 25 to 29; scales 6-37-6; 

 upper profile little concave; maxillary reaching beyond front of ventrals; 

 dorsal inserted just behind root of ventrals: pectorals reaching ventrals. 

 Silvery, with an indistinct round dark spot behind shoulder; generally 

 a baud-like blackish spot on root of caudal ; sometimes extending as a 

 dark band to humeral spot; this band sometimes silvery; sometimes both 

 band and spots absent. Mexico to Ecuador and Rio de la Plata, recorded 

 as common in Central America. (Rio Chisoy, Rio Guacalate, Huamuchal, 

 Cordova, etc.) (Rutilus, the roach, from rutilus, ruddy.) 



Tetragonoptervs rutilus, JENYNS, Zobl. Beagle, Fish., 125, 1842, Rio Parana. (Coll. Darwin). 



EFGENMANN, Proc. U. S. Nat. MUB., 1891, 52. 



Tetragonopterus tseniatus, JENYNS, L c., 126, 1842, Rio Janeiro. (Coll. Darwin.) 

 Tetragonoplertts fuscoauralus, CASTELNAU, Anim. Amer. Sud; Poise., 66, pi. 33, fig. 2. 1855, Bahia. 

 Tetragonopterus microstoma, GUNTHER, Cat., v, 323, 1864, Bahia. (Coll. Dr. Wucherer.) 

 Tetragonopterus fasciatus, GUNTHER, Cat., v, 322, 1864, (not of CUVIER& VALENCIENNES). 



555. TETRAGONOPTERUS PANAMENSIS, Gunther. 



Head 3 ; depth 2f ; eye 3 in head. D. 11; A. 28; scales 8-36-7. Simi- 

 lar to T. rutilus, but with more scales in a transverse series. Maxillary to 

 front of eye ; pectorals reaching a little beyond ventral base. Humeral 

 and caudal spots present, united by a silvery band. (Gunther.) Streams 

 about Panama and Lake Yzabal ; locally abundant. 



Tetragonoptei-us panamensK, GUNTHER, Cat., v, 324, 1864, Panama ; Yzabal. (Coll. Godman & 



Salvin.) 

 Tetragonopterus fischeri, STEINDACHNER, Flussfische Sudamerikas, i, 167, 1879, Mamoni River at 



Chepo, Colombia. 



556. TETRAGONOPTERUS MICROPHTHALMUS, Gunther. 



Head4i; depth 2f; eye about 4 in head. D. 11; A. 26 to 29; scales 

 7_36-8. Similar to T. rutilus, but the pectoral fin shorter, not reaching 

 base of ventral. Maxillary reaching front of eye. Silvery, with a band- 

 like spot at root of caudal ; usually a silvery lateral band. Guatemala, 

 (Lake Amatitlan), to Peru. (Gunther.) (//i/cp6f, small; 6<p#a/i//6f, eye.) 



Tetragonopterus microphthalmus, GUNTHER, Cat., v, 324, 1864, Lake Amatitlan ; Rio Rimac, 

 Peru. (Coll. Salvin.) 



557. TETRAGONOPTERUS (ERSTEDII, Kroyer. 



Head 4 ; depth 3 ; eye 3 in head. D. 11 ; A. 29 to 31 ; scales 7-37-8. 

 Mouth moderate, the maxillary about to front of eye ; pectorals about to 

 ventrals. Humeral and caudal spots present, connected by a faint silvery 

 band. Rio San Juan, Nicaragua. (Liitken.) (Named for Professor A. S. 

 Orsted of Copenhagen. ) 



Tetragonoplerus cersledii, KROYER, MS., LUTKEN, let. Bidrag, in, 229, 1874, Rio San Juan, Nica- 

 ragua. 



