454 EIGENMANN 



sci^nid^:. 



Pachyurus bonariensis Steindachner. 

 Many specimens. 



cichlid^:. 



Heros autochthon Giinther. 



Two specimens. 

 Geophagus australe Eigenmann, new species. (Plate XXIII, 



Fig. 7-) 



Closely related to G. duodecimspinosum = balzanii, from the 

 Paraguay. It differs from that species in the more pointed 

 snout, less steep profile, more rapidly descending dorsal slope, 

 longer, more slender caudal peduncle, narrower interorbital, 

 etc. It differs from its next nearest relative, G. gymdogenys, in 

 the scales of the cheek and in the color. 



Head 3 to 3.16; depth 2 to 2.4; D. xn to xiv, 10 or 11; 

 A. in, 8 ; lateral line 28 to 30 (16 to 18 + 10 to 12) ; 25 to 27 

 scales along the middle of the side. 



Subrhomboidal ; dorsal outline unequally arched, the highest 

 point at the origin of the dorsal. In G. balzanii the dorsal profile 

 is much more regularly arched from the tip of snout to end of 

 dorsal ; anterior profile convex in front of dorsal, nearly stra'ght 

 on head ; caudal peduncle rather long and slender, its depth 1 

 to 1.33 in its length ; interorbital very convex, the bony portion 

 3.5 in the head (2.5 in balzanii) ; cheeks with 3 series of scales 

 on their upper part, the lower portion naked (about 7 series in 

 balzanii) ; 7 or 8 tubercular gillrakers on lower half of arch ; 

 a single complete series of scales on the subopercle with a few 

 scales forming an imperfect second series below them. Eye 4 

 to 4.5 in head ; nares half way between tip of snout and eye 

 (distance of nares from tip of snout 1.6 in their distance from 

 eye in balzanii). 



Ventrals reaching the anal papilla or slightly beyond origin 

 of anal ; pectoral reaching to first anal spine or first anal ray ; 

 soft dorsal and anal high, reaching considerably beyond base of 

 caudal ; caudal lunate or but slightly emarginate, its base much 

 less densely scaled than in G. balzanii ; bases of dorsal and anal 

 with few scales ; fold of the lower lip not continuous. 



A dark area across back in front of the dorsal ; bases of some 



