522 MEMOIRS OF THE CARNEGIE MUSEUM 



Dorsal and anal spines graduated from the first to the last; dorsal and anal 

 rays graduated from the last to the first, the lobes at these points diverging, reaching 

 beyond the caudal; ventral filaments extending beyond the anal lobe; pectoral 

 not quite as long as the head; caudal emarginate, the outer rays prolonged. 



Silvery below, dusky above; a dark bar down from the eye, the bars of opposite 

 sides united in front of the ventrals; a dark bar from under the fifth dorsal spine 

 to in front of the anal; a dark bar connecting the dorsal and anal lobes; a dark bar 

 at the base of the caudal, fainter bands between each pair of the foregoing; caudal 

 with four cross-bands; dorsal lobe dark, the posterior part of the fin hyaline, its 

 base and two bars dark; anal lobe dark, three bars on the posterior part of the fin. 

 Ventral filaments white. 



FAMILY XXIV. POLYCENTRID.E. 



Polycentrus M filler and Troschel. 

 Polycentrus Muller and Troschel, in Schomburgk, Reisen, III, 1848, 622. 



Type, Polycentrus schomburgkii Muller and Troschel. 



Compressed, scaled; no lateral line; ventrals thoracic; teeth feeble; pseudo- 

 branchiae hidden; mandible without barbels; dorsal and anal spines numerous. 



354. Polycentrus schomburgki Muller and Troschel. 



Polycentrus schomburgkii Muller and Troschel, in Schomburgk, Reisen, III, 1848, 

 622; Horse Ichth., Ill, 1849, 25, pi. 5, fig. 2 (Essequibo).— Gunther, Cata- 

 logue, I, 1859, 396; III, 1861, 370 (Essequibo).— Regan, Proc. Zool. Soc. 

 London, 1906, i, 391, pi. 25, fig. 2 (Trinidad). — Eigenmann, Repts. Princeton 

 Univ. Exp. Patagonia, III, 1910, 466. 



Pohjcentrus tricolor Gill, Ann. Lye. Nat. Hist. N. Y., VI, 1858, 373 (Trinidad). 

 One specimen, 32 mm. Aruka River. (C. M. Cat. No. 2451.) 

 Two specimens, 27-30 mm. Cane Grove Corner. (C. M. Cat. No. 2422a-6; 



I. U. Cat, No. 12539.) 



One specimen, 35 mm. Georgetown trenches. (C. M. Cat. No. 2452.) 

 Thirty-nine specimens, 22-43 mm. Botanic Garden. (C. M. Cat. No. 



2417a-/; I. U. Cat. No. 12540.) 



Nine specimens, 30-50 mm. Maduni Creek. (C. M. Cat. No. 2418a-e; I. U. 



Cat. No. 12541.) 



Five specimens, 25-47 mm. Canal at Christianburg. (C. M. Cat. No. 



2419a-c; I. U. Cat. No. 12542.) 



Seven specimens, 47-55 mm. Kumaka. (C. M. Cat. No. 2420a-d; I. U. Cat. 



No. 12.543.) 



