ElGENMANN: COLLECTION OF FlSHES FROM PARAGUAY. 133 



terior border of the orbit ; 

 head 4; depth 2.25-2.75; 

 scales 7 to 9-35 to 39-6 or 7. 

 rutilus ceneus (Giinther) 26. 

 FFFF. Depth ^.^; bead 3.66; A. 

 29 ; scales 7—37—5 ; maxil- 

 lary long, equal to eye ; eye 

 2.5 in head; interorbital 

 3.66... cuvieri ( Liitken) 27. 

 DD. Dorsal over ventrals ; snout less than 4 in 

 the head ; interorbital flattish. A. 27, 

 beginning behind the dorsal. Depth 3 ; 

 head 4 ; lateral line 37. 



petenensis (Giinther) 28. 

 CC. No humeral spot. 



G. Dorsal behind ventrals ; snout about 4 in the 

 head ; interorbital convex. A. 26-30, be- 

 ginning under last ray of dorsal ; depth 

 3S}4 ; head 3^-4. Lateral line 36-40 ; 

 no maxillary teeth ; a silvery lateral band 

 which may become black on caudal. 



simus (Boulenger) 29. 

 GG. Head 2> l A~A l A » depth 2^-3; interorbital 

 much more than diameter of the eye. 

 Maxillary terminates below the anterior 

 margin of the eye ; origin of dorsal be- 

 hind the ventrals. A. 26-30 ; scales 

 6-35 to 37-6 to 8. 



fleruanus 11 (Muller & Troschel) 30. 

 BB. Caudal spot not continued on the middle rays. 



H . Scales in 15 rows, 7-36-7. Humeral and cau- 

 dal spots present, anal and ventral with broad 

 red margins ; eye 3% in the head, much 

 smaller than the convex interorbital. Maxil- 

 lary extending to an'erior margin of eye. 



A. 27-31 humilis (Giinther) 31. 



HH. Scales in 10-14 rows ; lateral line 34-38. 

 /. Head 4, or less than 4, in the length. 



J. A humeral spot. Maxillary reaching 

 anterior border of eye, not to end of 

 first suborbital. Head 3^-4 ; depth 

 2.4-2.7; A. 23-28; scales 6% or 

 7^-34 to 37-5^ to 6%. Two or 

 three maxillary teeth. 



fischeri (Steindachner) 32. 

 JJ. Maxillary ceases in front of the verti- 

 See also ceneus. 



