EIGENMANN: the freshwater fishes of BRITISH GUIANA 309 



In life the lower surface of the head is mottled witli orange, and the lower sides 

 and belly tinged with the same. Pectoral rays pink, yellow at the base; ventral 

 rays maroon, yellow at base; anal rays bright orange, the membrane olive at base; 

 caudal and adipose blackish blue, dorsal and upper sides similar, but a little lighter. 



Subfamily Crenuchin.^. 

 Crenuchus Giinther. 

 Crenuchus Gunther, Ann. and Mag. Nat. Hist., (3), XII, 1863, 448. 

 Type, Cremichus spilurus Giinther. 



Distinguished from all other American characins by its numerous, tricuspid 

 teeth, in a single series in each jaw, by the long dorsal fin, and by the presence 

 of an adipose fin. A broad depression between the eyes, but no frontal fontanel; 

 parietal fontanel large, ovate; gill-membrane free; lateral line incomplete. 



164. Crenuchus spilurus Giinther. 



Crenuchus spilurus GIjnther, Ann. and Mag. Nat. Hist., (3), XII, 1863, 448 

 (Essequibo); Catalogue, V, 1864, 365.— Steindachner, " Ichthyologische 

 Beitrage," v, 1876, 83 (Tabatinga, Hyavary).— Eigenmann and Eigenmann, 

 Proc. U. S. Nat. Mus., XIV, 1891, 59.— Eigenmann, Repts. Princeton Univ. 

 Exp. Patagonia, III, 1910, 430. 

 Five specimens, 43-56 mm. Georgetown trenches. (C. M. Cat. No. 1867a; 



I. U. Cat. No. 12152.) 



Three specimens, 40-45 mm. Kumaka. (C. M. Cat. No. 1868a; I. U. Cat. 



No. 12153.) 



Two specimens, 27-30 mm. Christianburg Canal. (C. M. Cat. No. 1869a; 



I. U. Cat. No. 12154.) 



One specimen, 43 mm. jNIud-flats below Wismar. (C. M. Cat. No. 1870a.) 



Two specimens, 35-43 mm. Essequibo, below Packeoo Falls. (C. M. Cat. 

 No. 1871a; I. U.Cat. No. 12155.) 



Two specimens, 35-39 mm. Maduni Creek. (C. M. Cat. No. 1872a; I. U. 

 Cat. No. 12156.) 



Two specimens, 40-43 mm. Aruka River. (C. M Cat. No. 1883a; I. U. 



Cat. No. 12157.) 



Two specimens, about 35 mm. Rockstone. (C. M. Cat. No. 2211.) 



Head 3-3.25; depth 3.2-3.5; D. 18; A. 11; scales 6-29 to 32-3, five to seven 



with pores; eye .75 in snout, 3.5 in head, a little more than interorbital. 



Compressed, with the dorsal and ventral outlines about equally arched; mouth 



