484 MEMOIRS OF THE CARNEGIE MUSEUM 



(Amucu). — Gunther, Catalogue, IV, 1862, 310 (Rio Negro; Guapore). — 



Steindachner, "Chromiden Amazonenstromes," 1875, 68 (Cudajas; San- 



tarem; Villa Bella; Coary; Teffe; Gurupa; Rio Xingu; Hyutay; Rio Negro; 



Guapore; Hyavary; Lake Hyanuary). — Eigenmann and Eigenmann, Proc. 



U. S. Nat. Mus., XIV, 1891, 70 (name only) .— Pellegrin, Bull. Mus. d'Hist. 



Nat., VIII, 1902, 182 (Marajo; Santarem; Manaos; Teffe; Tonantins); "Cich- 



lides," 164, in Mem. Soc. Zool. France, XVI, 1903, 200 (Santarem; Tonantins; 



Manaos). — von Ihering, Rev. Mus. Paulista, VII, 1907, 295. — Eigenmann, 



Repts. Princeton Univ. Exp. Patagonia, III, 1910, 469. 

 Chcetobranchus brunneus Heckel, Ann. Wiener Mus., II, 1840, 405 (Rio Negro). — 



Gunther, Catalogue, IV, 1862, 310 (Rio Negro). 

 Chcetobranchus robustus Gunther, Catalogue, IV, 1862, 310 (British Guiana). 

 Chromys ucayalensis Castelnau, Anim. Am. Sud, Poiss., 1855, 15, pi. 6, fig. 2. 



(adult female). 

 Geophagus bacliipinnis Cope, Proc. Acad. Nat. Sci. Phila., 1872, 251, pi. 11, fig. 



1, juv. (Ambyiacu). 



Two specimens, 102-224 mm. Rupununi. (C. M. Cat. No. 2298a; I. TJ. 

 Cat. No. 12464.) 



One specimen, 120 mm. Rockstone. (C. M. Cat. No. 2299.) 



One specimen, 238 mm. Lama Stop-Off. (C. M. Cat. No. 2300.) 



Two specimens, 212-217 mm. Maduni Creek. (C. M. Cat, No. 2301; I. U. 

 Cat. No. 12465.) 



Six specimens, 102-104 mm. Twoca Pan. (C. M. Cat. No. 2302a-c; I. U. 

 Cat. No. 12466.) 



Very similar to Acaropsis; distinguished by its gill-rakers. Head 2.66; depth 

 2.12-2.33; D. XIII, 13 or 14; A. 111,11 or 12; lateral line 16-18 + 10 or 11, scales 

 25-26 along a median series; eye 3.25-4 in the head, 1-1.5 in the interorbital ; 

 width of preorbital two-thirds to four-fifths of the diameter of the eye. 



Compressed and elongate; snout pointed; mouth large, the maxillary exposed 

 behind, not reaching to the vertical from the anterior margin of the eye ; maxillary- 

 premaxillary border 2.5 in the head; lips broad on the sides, the lower without a 

 frenum; caudal peduncle two-thirds as long as high. Gill-rakers 60-70 in the 

 lower arch, about eight-tenths as long as the eye. 



Four to six rows of scales on the cheeks; scales of the sides regular, none notably 

 decreased in size, feebly denticulate; one and one-half scales between the end of 

 the lateral line and the dorsal; dorsal and anal entirely naked, caudal scaled to 

 near its tip. 



