366 MEMOIRS OF THE CARNEGIE MUSEUM 



to the end of the middle rays. Dorsal, adipose, caudal, and anal punctate, the 

 latter sometimes most so along the base and tip. 



There are also in the collection: 



Cotypes, forty-one specimens, 21-68 mm. Amatuk. (C. M. Cat. No. 

 1050a-j; I. U. Cat. No. 11741.) 



Cotypes, seven specimens, 20-69 mm. Waratuk. (C. M. Cat. No. 1051a-6; 

 I. U. Cat, No. 11742.) 



Cotypes, three specimens, 23-40 mm. Savannah Landing. (C. M. Cat. 'No. 

 1052; I. U. Cat. No. 11743.) 



These differ from the typical specimens described in that the color along 

 the sides is in a dark band, instead of pinnately distributed, continued to the caudal 

 spot, which is continued to the end of the middle caudal rays. A. 23-25. Lateral 

 line 37, 37, 38, 38, 39, 40 in the six largest specimens from Amatuk. 



Phenacogaster Eigenmann. 

 Phenacogaster Eigenmann, Am. Nat,, XLI, 1907, 769. 



Origin of anal under origin of dorsal; lateral line complete; scales in front of 

 the ventrals in two series, overlapping in the middle. 



Type, Phenacogaster pectinatus (Cope). 



Range: Amazons and Guiana. 



Key to the Guiana Species of Phenacogaster. 

 a. Lateral spot large, subcircular; a scale in the angle of each pair of the ventral series of scales, except the two 

 pairs between the pectorals; scales with numerous radial strise; A. 33-37; scales 6-33 to 36-4 or 5; 

 premaxillary with four to seven teeth in the outer series and five to seven three-lobed teeth and one to 



three conical teeth. A caudal spot, not continued to the end of the middle rays megalostictus. 



aa. Lateral spot minute, inconspicuous; few if any scales in the angles of the pairs of scales along the ventral 

 surface; base and margin of anal dotted, the middle hyaline; scales with concentric striw; radial stria' 

 inconspicuous or absent. A. 37-40; scales 6-38 or 39-5; premaxillary with four tricuspid and five 

 conical teeth in the inner, series; no caudal spot microstictus. 



223. Phenacogaster megalostictus Eigenmann. (Plate LIII, fig. 3.) 

 Phenacogaster megalostictus Eigenmann, Ann. Carnegie Mus., IV, 1909, 28; Repts. 



Princeton Univ. Exp. Patagonia, III, 1910, 431. 



Type, 65 mm. Tumatumari. (Carnegie Museum Catalog of Fishes No. 

 1056.) 



Cotypes, fifty-nine specimens, 42-77 mm. Tumatumari, Lower Potaro River. 

 (C. M. Cat. No. 1057a-.?'; I. U. Cat, No. 11746.) 



Cotype, one specimen, 55 mm. Tukeit, (C. M. Cat. No. 1058.) 



