eigenmann: the FRESHWATER FISHES OF BRITISH GUIANA 439 



Caudal fin present; teeth in patches on both jaws; mouth large; snout not 

 tubular; eyes without free orbital margin. 



Key to the Guiana Species of Sternarchus. 

 a. Snout long, pointed, eye about in middle of the head; color uniform dark seal-brown with lighter spots at 



base of caudal and on forehead leptorhynchus. 



aa. Snout blunt, almost, if not, 3 in the head ; color black with a large white band entirely crossing body near the 

 end of the anal and at base of caudal; forehead white albifrons. 



281. Sternarchus leptorhynchus sp. no v. 



Type, 260 mm. Amatuk. (Carnegie Museum Catalog of Fishes No. 

 1763a.) 



Cotype, 160 mm. (length estimated; specimen broken). Amatuk. (I. U. 

 Cat, No. 12588.) 



Cotypes, 98 mm. Warraputa. (C. M. Cat. No. 1764a.) 



Head 4.9-5.2, greatest depth about 6.75 in the length to the end of the anal; 

 A. 158-160; snout 2.2-2.3, interorbital 6.5-7.5 in the head; eye about 9 in the 

 snout, 20-22 in the head, and 3-4 in the interorbital; thirteen to fifteen rows of 

 scales above the lateral line. 



Compressed and elongate; width of the head 3 or a little more, depth of the 

 head in occipital region 1.3-1.5 in the greatest depth of the body; anus about four 

 orbital diameters behind the vertical from the eye; dorsal profile of the head and 

 anterior sixth of the body abruptly sloping to snout, dorsal profile of the remainder 

 almost straight; ventral profile very weakly convex or almost straight. 



Snout heavy, rather long, and slightly rounded; mouth large, gape reaching 

 to just below the eyes; jaws equal, the lower included; teeth minute, conical, and 

 few, in two irregular, somewhat incomplete rows along each side of the lower jaw, 

 and in two irregular patches in the upper jaw. 



Caudal 3.8-4, pectoral 2-2.25 in the head; origin of pectoral immediately 

 behind gill-opening; origin of the anal about the length of the snout behind the 

 vertical from the eye. 



Color a uniform dark seal-brown ; a dirty white spot at the origin of the caudal ; 

 a more or less interrupted pale yellow streak running along the median dorsal line 

 from the tip of the snout to the middle of the back or farther (this streak a distinct 

 band in the smallest specimens) ; lips creamy white; fins hyaline, rays outlined with 

 dark brown. 



282. Sternarchus albifrons (Linnaeus). 



Gymnotus albifrons Linnaeus, Syst. Nat., ed. 12, I, 1766, 428. 



