EIGENMANN: the freshwater fishes of BRITISH GUIANA 275 



Heavy, tapering rapidly to the conical snout. Lower caudal lobe longer than 

 the upper. 



Dark above, lighter below; a black band from snout to end of middle caudal 

 rays, a narrower one parallel with it from the occiput to the base of the upper caudal 

 rays; a blackish band across the upper part of the anterior dorsal rays. 



Hemiodus M tiller. 

 Hemiodus MtJLLER, Monatschr. Akad. Wiss. Berlin, Juni, 1842, 324. 

 Hemiodopsis Fowler, Proc. Acad. Nat. Sci. Phila., 1906, 318 {microlepis). 



Type, Hemiodus crenidens Miiller = Hemiodus unimaculedus (Bloch). 



Teeth in the upper jaw only, pluricuspid, in a horseshoe-shaped series; mouth 

 inferior; gill-membranes free from each other and from the isthmus; fontanels 

 large; scales below the lateral line of the same size as those above it. 



Key to the Guiana Species of Hemiodus. 

 a. Sides with three black cross-bands; a black spot on the caudal peduncle, continued to the end of the lower 



caudal lobe; upper caudal lobe ^ith a weaker black band quadrimaculatus. 



aa. A black spot on the middle of the sides, half-way between dorsal and adipose, and a black band extending 

 from it to the tip of the lower caudal lobe semitaeniatus. 



132. Hemiodus quadrimaculatus Pellegrin. (Plate XXXVI, fig. 2.) 



" Wuranali " of the Wacusi Indians. 



Hemiodus quadrimaculatus Pellegrin, Bull. Mus. d'Hist. Nat., XIV, 1908, 344 



(Camopi R., Fr. Guiana). — Eigenmann, Repts. Princeton Univ. Exp. Pata- 

 gonia, III, 1910, 423. 



One specimen, 110 mm. Tukeit. (C. M. Cat. No. 1926.) 



Three specimens, 55-70 mm. Amatuk. (C. M. Cat. No. 1927; I. U. Cat. 

 No. 12187.) 



Thirty-four specimens, the largest 81 mm. Tumatumari, in pools above the 

 cataract. (C. M. Cat. No. 1928o-e; I. U. Cat. No. 12188.) 



Six specimens, 57-125 mm. Crab Falls. (C. M. Cat. No. 1929« and 1930; 

 I. U. Cat. No. 12189.) 



A conspicuously marked species, evidently closel}^ related to, if not identical 

 with, Hemiodus quadrimaculatus Pellegrin. 



Head about 4; depth 4-4.4; D. 12; A. 10; scales 7 or 8-44 to 46-4 or 5. 

 Eye 1.3 in snout, 3.3 in head, 1 in interorbital. 



Dorsal and ventral outlines equally arched, the snout pointed, projecting 

 considerably; preventral area broad, with a regular median series of scales. 



Twenty to twenty-four teeth in the upper jaw. 



