60 



THE AMERICAN CHARACIDAE. 



Tetragorwpterus schomburgkii Cuvier & Val., Hist. nat. poissons, 1848, 22, p. 137 (Essequibo) 1 . 

 Tetrugonopterus ortonii Gill, Proc. Acad. nat. sci. Phil., 1870, p. 92 (Brazil ?) ; Cope, Proc. Amer. philos. 

 soc, 1869, 11, p. 566 (Pebas). 



Habitat. — Guianas and Amazons, Rio San Francisco. 



Specimens examined. 2 



Head 3.2-3.66; depth l|-2; D. 11; A. usually 32 or 33. 3 Scales 7-29 to 



1 The type, one specimen in bad condition, from the Essequibo, 160 mm. A. 32; scales large, 

 about 30; depth a little less than 2; head 3.66; eye very large, about 2.33 in the head, about equal to 

 the convex interorbital; maxillary with three small teeth; pectorals extending to ventrals; anal not 

 falcate, dorsal behind the vertical from the ventrals, not reaching the adipose. No occipital process. 

 The nape of the specimen seems to have met with an accident and it is difficult to determine how much 

 of the difference between it and the types of T. rufipes is due to bad preservation and to the mutilation. 

 The eye is much larger than in the type of T. rufipes. Caudal spot not continued on the middle rays. 



2 1 have also examined the types of T. artedii and T. schomburgkii. 



3 Out of twenty-one one has twenty-eight, one has thirty, four have thirty-one, eight have thirty- 

 two, five have thirty-three, and two have thirty-four anal rays. 



