EIGENMANN: the freshwater fishes of BRITISH GUIANA 403 



257. Asiphonichthys hemigrammus sp. nov. (Plate LX, fig. 4.) 



Type unique, 27 mm. (iluck Island. (Carnegie Museum Catalog of 

 Fishes No. 2137.) 



A second specimen was collected by Dr. Ellis on CUuck Island. 



Head 3.5; depth 3; D. 10; A. 45; scales 10-48-7, five scales with pores; eye 

 .75 in snout, 3 in head, .75 in interorbital. 



Compressed, snout pointed, profile depressed over the eyes; maxillary extend- 

 ing to end of first suborbital; nearly the entire lower half of the cheeks naked; 

 gill-rakers 5 + 8, those of the upper arch short, those of the lower large and long. 



Scales without longitudinal striae, fins naked; scales reduced in size on the 

 back in front of the dorsal. 



Anterior spine of the clavicle claw-like, directed upward and forward; the 

 posterior spine scale-like; pectoral without developed rays; origin of dorsal very 

 little nearer to tip of snout than to caudal, behind the vertical from the origin of 

 the anal; ventrals reaching to the base of the eighth anal ray. 



A black spot above and behind the last pore of the lateral line; a spot on the 

 end of the caudal peduncle. 



In the two specimens mentioned above the pectoral is without developed rays. 

 In a third specimen, probably belonging to this species (38 mm.), the pectorals are 

 normally developed. 



Cynopotamus Cuvier and Valenciennes. 

 Cynopotamus Cuvier and Valenciennes, Hist. Nat. Poiss., XXII, 1848, 317. 

 Cyrtocharax Fowler, Proc. Acad. Nat. Sci. Phila., 1906, 454. 



Type, Hydrocyon argenteus Valenciennes. 



Teeth of lower jaw in a single series, consisting of four canines in front (of 

 which the third is largest) and numerous small teeth on the sides; premaxillary 

 teeth in two series, a canine at each end; maxillary without canines. Lateral 

 line complete, scales very small. No opercular spine. Clavicle slightly notched, 

 the lower edge not blade-like, without spines. 



I have examined the type of Cynopotamus argenteus (22 mm. long, Buenos 



Aires) in the Jardin des Plantes. I was unable to find an inner series of teeth in 



the lower jaw. 



258. Cynopotamus essequibensis sp. nov. 



Type, one specimen, 175 mm. Potaro Landing. (C. M. Cat. No. 2146.) 



Cotype, one specimen, 180 mm. Tumatumari. (C. M. Cat. No. 2147.) 



Cotypes, seven specimens, 53-170 mm. Rockstone. (C. M. Cat. No. 2148- 



a-c] I. U. Cat. No. 12319.) 



