EIGENMANN: THE FRESHWATER FISHES OF BRITISH GUIANA 429 



Ground-color stone-gray to buff; body closely pigmented with minute purple 

 spots, which are more abundant dorsally; a yellowish white lateral streak of 

 variable intensity and width — being almost wanting in some specimens — beginning 

 a little ventrad of the lateral line, at a point about half the total length from the 

 head, and continuing well out on the caudal appendage; a bluish black spot about 

 twice the size of the eye at the origin of the lateral line; head rather dark above; 

 fins hyaline. 



Specimens were found in the catch from Potaro Landing in particular, as well 

 as at Aruka and Amatuk, which were very much darker than the average, being a 

 dark blue. Since the ground-color was darker the lateral stripe appeared more 

 strikingly white in these specimens. 



Eigenmannia Jordan and Evermann. 

 Sternopygus Muller and Troschel, Horae Ichth., Ill, 1849, 13. 

 Cryptops Eigenmann, Ann. N. Y. Acad. Sci., VII, 1894, 626 (preoccupied). 

 Eigenmannia Jordan and Evermann, Bull. U. S. Nat. Mus. No. 47, I, 1896, 341. 



Type, Sternopygus humbolaltii Steindachner. 



No free orbital margin; teeth in patches on both jaws; snout not produced; 

 no caudal fin, tail beyond the anal, slender, cylindrical, and pointed. 



The two species known from British Guiana may be distinguished by the 

 following key: 



Key to the Guiana Species op Eigenmannia. 

 a. Eye large, its diameter longer than the maxillary; caudal appendage long, equal to almost half the total 



length macrops. 



aa. Eye medium, its diameter equal to the maxillary; caudal appendage 3.25-4.75 in total length, .virescens. 



273. Eigenmannia macrops (Boulenger) . 

 Sternopygus macrops Boulenger, Ann. and Mag. Nat. Hist., (6), XX, 1897, 305 



(British Guiana). 

 Eigenmannia macrops Eigenmann and Ward, Proc. Wash. Acad. Sci., VII, 1905, 



172. 

 Eigenmannia microps Eigenmann, Repts. Princeton Univ. Exp. Patagonia, III, 



1910, 449. 



Thirty-two specimens, 165-200 mm. Rockstone. (C. M. Cat. No. 1804a-e; 

 I. U. Cat. No. 12601.) 



Twelve specimens, 165-180 mm. Tumatumari. (C. M. Cat. No. 1805a-d; 

 I. U. Cat. No. 12602.) 



