South- American Characinoid Fishes. 173 



(without caudal) , the length of the head four times to four 

 times and one third. The diameter of the eye exceeds the 

 length of the snout and equals the width of the interorbital 

 space ; no well-developed adi^iose eyelid. The maxillary 

 extends beyond the anterior margin of the eye. The vertical 

 from the origin of the dorsal fin falls behind the root of the 

 ventrals, and the origin of the anal behind the last dorsal 

 ray ; the pectoral reaches the root of the ventrals, or not quite 

 so far. A blackish spot behind the shoulder ; a silvery 

 lateral band, turning to black on the tail ; dorsal, anal, and 

 caudal fins finely speckled with black. 



Total length 88 millim. 



This species resembles much in coloration and proportions 

 the young T. rutilus^ Jen., from which it is easily distin- 

 guished by the number of dorsal and anal rays and the larger 

 scales. 



Fifteen specimens, from San Lorenzo, Rio Grande do Sul ; 

 collected by Dr. v. Ihering. 



Tetragonopterus Luetkenii. 

 D. 2/9. A. H/21-22. L. lat. 33-35. L. transv. 10-11. 



Lateral line not continued to the tail, extending on from ten 

 to sixteen scales. The greatest depth of the body is contained 

 twice and one third to twice and a half in the total length 

 (without caudal), the length of the head four times. The 

 diameter of the eye exceetls the length of the snout and is 

 less than the width of the interorbital space ; no well-deve- 

 loped adipose eyelid. The maxillary extends to or somewhat 

 beyond the anterior margin of the eye. The vertical from 

 the origin of the dorsal fin falls behind the root of the ventrals, 

 and the origin of tiie anal just below or slightly behind the 

 last dorsal ray ; the pectoral reaches the root of the ventrals. 

 A round black spot behind the shoulder and another on the 

 base of the caudal, the median rays of which are black ; a 

 silvery lateral band ; dorsal and anal fins finely speckled with 

 black. 



Total length 85 millim. 



Four adult and three young specimens from San Lorenzo, 

 Rio Grande do Sul ; collected by Dr. v. Ihering. 



Three other species, from the province Rio Grande do Sul, 

 were sent by Dr. v. Iliering. I refer them to T. maculatus. 

 L. {=^ microstoma^ Hcnsel, nee Giinth.), 7'. rnfilus, Jen., and 



