324 CHABACINID^SS. 



14. Tetragonopteras microphthalmus. 

 D. 11. A. 26-29. L.lat. 35-37. L. transv. 7/8. 



Very similar to T. microstoma, but with shorter pectoral fins. 



The height of the body is contained twice and three-fourths in the 

 total length (without caudal), the length of the head four times or 

 four times and one-third ; interorbital space very convex, its width 

 being much more than the diameter of the eye, which is nearly one- 

 fourth of the length of the head. The upper profile is very little 

 concave above the parietal region. The maxillary does not extend 

 to the end of the first infraorbital bone, and terminates in the vertical 

 from the front margin of the eye. The origin of the dors<d fin is 

 vertically behind the root of the ventrals. The pectoral does not 

 extend to the ventral. A band-like blackish spot on the root of the 

 caudal fin ; generally a silvery band along the side. 



Peru and Guatemala. 



a-b. Adult. Pacific coast of Guatemala. From Mr. Salvin's Collection. 

 e-d. Adult. Lake of Amatitlan. From Mr. Salvin's Collection. 

 e-i. Adult and half-grown, Rio Rimac*. Presented by "W. Nation, 

 Esq. 



15. Tetragonopteras panamensis. 



D. 11. A. 28. L.lat. 35-36. L. transv. 8/7. 



Very similar to T. microstoma, but with a greater number of series 

 of scales above and below the lateral line. 



The height of the body is contained twice and two-thirds or twice 

 and three-fourths in the total length (without caudal), the length of 

 the head four times or three times and three -fourths. Interorbital 

 space convex, its width being more than the diameter of the eye, 

 which is two-sevenths of the length of the head. The upper profile 

 of the head is somewhat concave above the parietal region. The 

 maxillary terminates in the vertical from the front edge of the eye. 

 The origin of the dorsal fin is vertically behind the root of the ven- 

 trals. The pectoral reaches to, or a little beyond, the base of the 

 ventrals. Humeral and caudal spots present, united by a silvery 

 longitudinal band. 



Panama, Guatemala. 



a. Fine specimen, 4 inches long. Pacific coast of Panama. From 



the Collection of Messrs. Godman and Salvin. 

 b-d. From 2| to 3 inches long. Yzabal. From the Collection of 



Messrs. Godman and Salvin. 



16. Tetragonopteras dichrouras. 



Kner, Denkschr. Acad. Wiss. Wien, 1859, xvii. p. 177. taf. 9. fig. 21. 

 D. 10. A. 25-26. L.lat. 36-38. L. transv. — . 



3-4 



The height of the body is contained twice and two-thirds in the 



* Valenciennes also has examined Tetragonopteres from the Rio Rimac, but he 

 refers them to T. scabrijrinnis, Jenyns, a species different from T.microphthalmus. 



