ANNOTATED LIST OF THE SPECIES 335 
Iquitos 
As in the preceding regarded as a good species by Dr. G. 8. Myers, who has 
seen the paper. D. 18; A. 38; scutes 28; rakers 9 + 13. 
Family XVI: Osteoglossidae 
Genus 192: OSTEOGLOSSUM Vandelli 
Osteoglossum (Vandelli) Cuvier, 1829, Régne Anim., ed. ii, II, 328; 
Agassiz, 1829, Sel. Gen. et Spec. Pise. Bras., 47; 
Figenmann and Eigenmann, 1891, Proc. U. S. Nat. Mus., XIV, 63; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 453; 
Eigenmann, 1912, Mem. Carnegie Mus., V, 449. 
Type: Osteoglossum bicirrhosum Vandelli 
The Amazons northward 
Elongate, body compressed roundly above and drawn to a knife edge ventrally, 
tapering toward the tail; mandible extremely long and narrow, the gape nearly 
vertical, bearing a pair of mental barbels which extend forward while swimming; eye 
large, scales large and conspicuous. 
469. OSTEOGLOSSUM BICIRRHOSUM Vandelli 
Osteoglossum bicirrhosum Vandelli, 1829, Sel. Gen. et Spec. Pisc. Bras., 45; 
Giimther, 1868, Cat. Fish. Brit. Mus., VII, 378; 
Cope, 1871, Proc. Acad. Nat. Sci. Phila., X XIII, 257, Ambyiacu; 
Cope, 1878, Proc. Amer. Phil. Soc., XVII, 695; 
Steindachner, 1882 (1883), Denksch. KIx. Akad. Wiss. Wien, XLVI, 16, Rio Huallaga; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 453; 
Figenmann, 1912, Mem. Carnegie Mus., V, 450; 
Fowler, 1939 (1940), Proc. Acad. Nat. Sci. Phila., XCI, 221, fig. 1, two, 305 and 350 mm., 
Contamana, Morrow collection. 
Range that of the genus 
15730, 1, 8305 mm., mouth Rio Pacaya, Allen, September, 1920. 
15731, 1, 230 mm., Lago Cashiboya, Allen, August, 1920, specimen sent to U.S. National Museum. 
15953, 1, 325 mm., Iquitos, Morris, 1922. 
This species is known throughout eastern Peru under the name which may be 
rendered in the Spanish as arahwana (arowana of the Guiana Indians, as reported 
by Eigenmann, 1912). This appears to be a name given by the aborigines of Guiana 
rather than Peru, first borrowed by the white inhabitants of that country, and 
transmitted to other remote regions by them since the Conquest. 
Characterized by the vivid colors, large scales, compressed body, and two 
short, but prominent barbels. The use of the barbel is debated, but I have seen 
them extended forward while in motion. 
They inhabit the clearer waters of the backwater lakes and bayoux, and seek 
the surface, at least a considerable part of the time. 
