248 MEMOIRS OF THE CARNEGIE MUSEUM 



Twenty-four specimens, 73-151 mm. Gluck Island. (C. M. Cat. No. 1499a-e; 

 I. U. Cat. No. 11934.) 



Eight specimens, 67-183 mm. Rockstone. (C. M. Cat. No. 1500a; I. U. 

 Cat. No. 11935.) 



Four specimens, 77-135 mm. Tumatumari. (C. M. Cat, No. 1501a; I. U. 

 Cat. No. 11936.) 



Six specimens. Rupununi. (C. M. Cat. No. 1502a-6; I. U. Cat, No. 11937.) 



Head 5.33-5.5; width of head 1.4-1.66 in its length; eye 6-6.5 in the head, 

 interorbital 4.33, snout 2; width at first anal ray 4.5-5.33 in the distance of the 

 anal from the caudal; scutes 18 + 13 to 16 + 15, the keels entirely united on the 

 posterior scutes. 



Lips papillose, their margins fringed, more in the young, less in the adult; 

 free part of barbel equal to eye. Head and scutes without keels. Seven to ten 

 teeth on each side of the upper jaw, seven to nine on each side of the lower. 



Lower surface of head naked ; a narrow orbital notch. 



Anal plate bordered by three plates; eleven to sixteen plates in the ventral 

 buckler; three series of plates between the lateral series, which in the posterior 

 part of the belly are frequently so united as to form a transverse scute; middle 

 plate sometimes more distinct, Armature developed to between the anterior angle 

 of the gill-opening. 



Pectoral truncate, the outer ray sometimes slightly produced, reaching about 

 to origin of ventrals. Outer ventral ray sometimes produced, reaching to base of 

 first or beyond base of last anal ray. Dorsal spine a little longer than the head; 

 caudal lunate, the upper ray much, and the lower sometimes less, produced. 



Pores of the head black; a dark spot in front of the dorsal, not quite equal to 

 the eye, margined by a lighter one, and this flanked by a dark streak on each side, 

 having the appearance of an obscure ocellus, becoming very obscure in the largest 

 specimen. Dorsal surface marbled, four or five dark bands behind the dorsal, 

 evident even in the largest specimens. Fins spotted, tip of caudal blackish, the 

 latter with cross-bars, a basal and submarginal bar in the largest, and several in the 

 smaller, in which the caudal is much darker, sometimes nearly black; a small dark 

 spot on either side of the base of the first anal ray. 



113. Loricariichthys platyurus (Muller and Troschel). (Plate XXX, fig. 4; 



Plate XXXI, fig. 3.) 

 Loricaria platyura Muller and Troschel, in Schomburgk, Reisen, III, 1848, 631 

 (Rupununi). — Eigenmann, Repts. Princeton Univ. Exp. Patagonia, III, 1910, 

 415. 



