eigenmann: the FRESHWATER FISHES OF BRITISH GUIANA 481 



Ground-color light brown, only a little darker above; everywhere, except on 

 the lower part of the head and at the base of the pectoral, thickly peppered with 

 dark chromatophores. Pectoral intensely black; caudal and spinous dorsal also 

 black; anal, soft dorsal, and mid- ventral rays very dusky. Two innermost and 

 the elongate outer rays of the ventral creamy. Lining of the opercle blackish. 

 Scales above the lateral line outlined with dusky. 



Family XXII. CENTROPOMID.E. 



Centropomus Lacepede. 



Centropomus Lacepede, Hist. Nat. Poiss., IV, 1802, 248 (sp.). — Cuvier and 

 Valenciennes, Hist. Nat. Poiss., II, 1828, 102 (undecimalis). 



Oxylabrax Bleeker, Arch. Neerl. Sci. Nat., XI, 1876, 264 (undecimalis). 



Macrocephalus (ex Browne) Bleeker, Arch. Neerl. Sci. Nat., XI, 1876, 336 (un- 

 decimalis). 



Type, Sciama undecimalis Bloch. 



Elongate fishes, with a pointed snout and projecting lower jaw. 

 Scales ctenoid, lateral line conspicuous, continued on the middle caudal rays; 



caudal forked; head depressed, lower jaw projecting; the second anal spine large. 



Key to the Guiana Species of Centropomus. 

 a. Preorbital smooth or with fine teeth; second anal spine scarcely longer than the third, not reaching beyond 

 the tip of the first soft ray, not nearly reaching caudal. Maxillary extending beyond the middle of the 

 eye. Lateral line black; lower caudal lobe dusky; sides silvery or dusky. About sixty-five pores in the 



lateral line undecimalis. 



aa. Preorbitals with retrorse spines; second anal spine much longer than the third, extending far beyond the 

 tip of the first soft ray, reaching the caudal. Maxillary not extending beyond the middle of the eye. 

 Lateral line not black; sides silvery. About fifty pores in the lateral line ensiferus. 



325. Centropomus undecimalis (Bloch). 



Sciama undecimalis Bloch, Ausl. Fische, VI, 1792, 60, pi. 303. 



Platyccphalus undecimalis Bloch and Schneider, Syst. Ichth., I, 1801, 59. 



Centropomus xindecimalis, part, Cuvier and Valenciennes, Hist. Nat. Poiss., II, 

 1828, 102, pi. 14 (Rio de Janeiro; Lima; St. Domingo; Martinique). — Gun- 

 ther, Catalogue, I, 1859, 79 (Bahia; Pernambuco; Surinam; Demerara; 

 Santo Domingo; Jamaica). 



Centropomus undecimalis Guicheneau, in la Sagra, Hist. Cuba, Poiss., 1853, 9.— 

 Vaillant and Bocourt, Miss. Sci. au Mex. et dans l'Am. Cent., Poiss., 1874, 

 17, pi. 2, fig. 1. — Steindachner, "Fisch-Fauna Magdalenen-Stromes," 1878, 5. 

 — Jordan and Gilbert, Synopsis Fishes North America, 1882, 528. — Ever- 



