66 



PROCEEDINGS OF THE NATIONAL MUSEUM 



2b. Rear margin of eye midway between tip of snout and occiput; snout con- 

 tained more than 2 times in postorbital length of head. 

 3a. Distance from posterior nostril to eye contained 9 to 14 times in length 

 from snout to occiput; pore above posterior nostril lying behind a 

 vertical line through rear of nostril, or this hne bisecting the pore, the 

 latter separated from nasal opening by an isthmus of skin; tail behind 

 anal compressed and ending rather abruptly not gradually tapering to 

 a rounded point and contained about 5 to 6 times in total length; snout 

 2.2 to 2y3 into postorbital length of head (Rio Condoto; Panama; 



Maracaibo Basin) Hypopomus occidentalis Regan 



3b. Distance from posterior nostril to eye contained about 25 to 32 times in 

 distance from snout to occiput; pore above posterior nostril lying close 

 to margin of that nostril and bisected by a line through middle of pos- 

 terior nostril or the pore is just in front of this line; snout very bluntly 

 rounded, 2.5 to 2.8 times in postorbital length of head; tail very little 

 compressed, tapering to a point and contained about bYz to 6 times in 

 total length (Caripito, "Venezuela) Hsrpopomus beebei Schuitz 



a 



Figure 9. — Arrangement of cephalic pores and position of eye: a, Hypopomus occidentalis 

 Regan; b, Hypopomus beebei Schuitz. Sketches by author. 



HYPOPOMUS OCCIDENTALIS Regan 



Figure 9, a 



Hypopomus occidentalis Regan, Ann. Mag. Nat. Hist., ser. 8, vol. 14, p. 32, 1914 

 (Rfo Condoto, Colombia). 



? Hypopomus brevirosiis Ihering, Rev. Mus. Paulista, vol. 7, p. 281, 1907 (Vene- 

 zuela) . 



U.S.N. M. No. 121586, 38 specimens, 63 to 167 mm., Rio San Pedro at bridge, 

 Motatdn system, March 20, 1942. 



U.S.N. M. No. 121584, 8 specimens, 49 to 115 mm., Rfo San Juan, 12 km. south 

 of Rosario, Februarj'^ 26, 1942. 



U.S.N. M. No. 121585, 11 specimens, 70 to 175 mm., Rio San Juan at bridge 

 south of Mene Grande, tributary of Rfo Motatdn, March 20, 1942. 



HYPOPOMUS BEEBEI Schnltz 



Plate 2; Figure 9, b 



Hypopomus beebei Schultz, Zoologica, vol. 29, No. 1, p. 40, fig. 1, pi. 1, fig. 4, 1944 

 (Caripito, Venezuela). 



