12 Dr. A. Giinther on the 



the eye. Each ray of the caudal, pectoral, and ventral fins is 

 crossed by a number of short black streaks, whilst the dorsal 

 fin is crossed by six or seven black zigzag stripes. 

 One specimen, 9^ inches long, from Cordova. 



35. Trichomycterus dispar, Tschudi (= T. cordovensis, 

 Weyenbergh). 



Received from Cordova. 



36. Macrodon intermedins, Gthr. (an = ilf. auritus, C.&V.?). 



37. Curimatus platanus, sp. n. 

 D. 11. A. 9. L. lat. 55. L. transv. 12/11. 



Allied to Curimatus Alberti, but with considerably smaller 

 scales. The height of the body is contained thrice and one 

 third in the total length (without caudal) ; the length of the 

 head nearly four times. The upper profile is slightly concave 

 above the occiput ; snout as long as the eye, the diameter 

 of which is a little more than half the width of the inter- 

 orbital space. An anterior and posterior eyelid. The origin 

 of the dorsal fin is nearer to the extremity of the snout than 

 to the base of the caudal. The pectoral terminates at some 

 distance from the caudal, its length being two thirds of that 

 of the head. Ventral not extending to the vent. Abdomen 

 rounded in front of and behind the ventrals. Scales not 

 ciliated. Silvery ; a more or less distinct black spot on the 

 root of the caudal. 



Two specimens 6 inches long. 



38. Prochilodus lineatus, Val. 



39. Anostomus vittatus, C. & V. 



40. Leporinus obtuside?is } Val. 



41. Tetragonopterus orbicularis, C. & V. 



42. Tetragonopterus fasciatus, Cuv. (= T. Cuvieri, 



Ltk., = T. rutilus, Jen.). 



43. Tetragonopterus microstoma, Gthr. 



44. Tetragonopterus petenensis, Gthr. 

 From the Rio Negro, Argentine Rep. 



45. Tetragonopterus abramis, Jen. 



46. Tetragonopterus cordovce, sp. n. 



D. 11. A. 26. V. 8. L. 1. 45. L. tr. 9/10. 



The height of the body is one third of the total length 

 (without caudal), sometimes a little more or less ; the length of 



