eigenmann: the FRESHWATER FISHES OF BRITISH GUIANA 297 



Cotypes, two specimens, 72-77 mm. Amatuk. (C. M. Cat. No. 1863a; I. U. 

 Cat. No. 12150.) 



Cotypes, two specimens, 78-90 mm. Tumatumari. (C. M. Cat. No. 1864a; 

 I. U. Cat. No. 12151.) 



Very similar to A. trimaculatus, but the snout longer and slenderer, the 

 lips more prominent, and the color different. 



Head 3.4-3.5; depth 3.3-4; D. 12; A. 10; scales 5-39 or 40-4. Eye 1.75 in 

 snout, 4 in head, 1.5 in mterorbital; 1.5, 3.5, 1.1, respectively, in a specimen 77 

 mm. long. 



Width about half the depth; dorsal profile convex to the nape, thence very 

 concave to the very prominent lips; snout subcircular in cross-section, much longer 

 than the post-orbital part of the head; opercle faintly striate in the largest. 



Four teeth on each side of each jaw; the two lateral teeth of the lower jaw 

 tricuspid, the middle ones truncate; the two outer ones of the upper jaw tricuspid, 

 the middle ones bifid, the two points frequently unequal. 



Dorsal rounded, its highest ray 5.75-6 in the length; its origin equidistant 

 from tip of snout and base of middle caudal rays; caudal deeply forked, its upper 

 lobe about 4 in the length; anal slightly emarginate, the longest ray reaching the 

 tip of the last; ventrals reaching about half-way to middle of anal, pectorals more 

 than half-way to ventrals. 



Light brown to nearly black; four spots along middle of sides, the first on 

 and below the fourth scale of the lateral line, the second from the fifteenth or 

 seventeenth scale, the third on the twenty-sixth and twenty-seventh, the last at 

 the end of the line. About twelve cross-bars, not evident on dark individuals, the 

 part of the bars below the lateral line shifted forward or backward. Iridescent 

 spots on the scales. 



Schizodon Agassiz. 

 Schizodon Agassiz, Selecta Gen. et Spec. Pise. Bras., 1829, 66, pi. 36. 



Type, Curimatus fasciatus Spix. 



Like Anostomus, but with the mouth terminal, the snout not produced, elliptical 

 in cross-section; lower teeth short and broad. 



155. Schizodon fasciatus (Spix). 



Curimatus fasciatus Spix, Selecta Gen. et Spec. Pise. Bras., 1829, pi. 36. 



Schizodon fasciatus Agassiz, Selecta Gen. et Spec. Pise. Bras., 1829, 66. — Schom- 

 burgk, Fishes Brit. Guiana, I, 1841, 252, pi. 26 (Rio Branco). — Muller and 

 Troschel, Horse Ichth., I, 1845, 10, pi. 1, figs. 5-5a; in Schomburgk, Reisen, 



