EIGENMANN: THE FRESHWATER FISHES OF BRITISH GUIANA 333 



Tetragonopterus unilineatus Eigenmann and Eigenmann, Proc. U. S. Nat. Mus., 



XIV, 1891, 54.— Ulrey, Ann. N. Y. Acad. Sci., VIII, 1895, 285 (Para, Brazil). 



—Gilbert. Proc. Wash. Acad. Sci., II, 1900, 163 (Pernambuco). 

 Tetragonopterus hemigrammus unilineatus Regan, Proc. Zool. Soc. London, 1906, 



384 (Trinidad). 

 Hemigrammus unilineatus Eigenmann, Repts. Princeton Univ. Exp. Patagonia, 



III, 1910, 436. 



Five specimens, 28-38 mm. Para, Brazil. (I. U. Cat. No. 5779.) 



One specimen, 40 mm. Los Castillos. (I. U. Cat. No. 10801.) 



One hundred and ten specimens, 35-48 mm. Creek in Mora Passage. (C. M. 

 Cat. No. 1440a-./; I. U. Cat, No. 11898.) 



Twenty-two specimens, 31-41 mm. Creek in Barima River. (C. M. Cat. 

 No. 1441a-e; I. U. Cat. No. 11899.) 



Eighty-six specimens, 23-48 mm. Aruka River. (C. M. Cat. No. 1442a-.?'; 

 I. U. Cat. No. 11900.) 



Seven specimens, 32-52 mm. Issorora mud creek. (C. M. Cat. No. 1443a-6; 

 I. U. Cat. No. 11901.) 



Sixteen specimens, 36-53 mm. Mud-flats in Demerara River, below Wismar. 

 (C. M. Cat. No. 1444a-e; I. U. Cat. No. 11902.) 



One specimen, 37 mm. Georgetown trenches. (C. M. Cat. No. 1445a.) 



Four specimens, 41-47 mm. Wismar. (C. M. Cat. No. 1446a; I. U. Cat. 

 No. 11903.) 



Five specimens, 35-47 mm. Kumaka, Demerara. (C. M. Cat. No. 1447a-6; 

 I. U. Cat. No. 11904.) 



Distinguished by having an oblique black line from the base of the first to 

 the tip of the fourth and fifth anal rays. Six conical and tricuspid teeth in the 

 maxillary. Second suborbital leaving a narrow naked margin below. 



Head 3.75; depth 2.75-3; D. 11; A. 23-27; scales 5-32 to 34-3 to 4.5; eye 

 2.25 to 2.5 in the head; interorbital narrower than the eye, 3 in the head. 



Dorsal black, except the tips of the anterior five or six rays. An oblique 

 black line on the anal from the base of the first to the tips of the fourth and fifth 

 rays. Humeral spot vertically elongate, often faint and sometimes lacking. No 

 caudal spot. Lateral stripe narrow. Scales of the back outlined with dusky. 



190. Hemigrammus erythrozonus Durbin. (Plate XLVIII, fig. 2.) 



Hemigrammus erythrozonus Durbin, Ann. Carnegie Mus., VI, 1909, 56. — Eigen- 

 mann, Repts. Princeton Univ. Exp. Patagonia, III, 1910, 436. 



