556 PROCEEDINGS OF THE NATIONAL MUSEUM voL.no 



Specimens examined : Twenty-eight, from the following localities : 



Trinidad: Prince's Town, 4 (AMNH, includes types of speciosus and trinitatis) ; 

 Caura, 2 (AMNH); Mayaro, 1 (BM, type of splendens); Cumaca, 1 (AMNH); 

 St. Pats, 1 (AMNH); San Rafael, 1 (CNHM). 



Venezuela: Quebrada Seca, Sucre, 5 (AMNH, includes types of palmarius 

 and f ulviv enter) ; Neveri, Sucre, 3 (AMNH); San Rafael, Sucre, 1 (CM); Rfo 

 Yurudn, Bolivar, 1 (AMNH); Auyan-tepui, Bolivar, 2 (AMNH, includes type 

 of auyantepui) ; Arabupu, Mt. Roraima, Bolivar, 2 (AMNH). 



British Guiana: Kartabo, 4 (BM, type of guianae; AMNH, 3). 



Oryzomys concolor superans Thomas 



(Ecomys superans Thomas, Ann. Mag. Nat. Hist., ser. 8, vol. 8, p. 250, 1911; ser. 



10, vol. 2, p. 261, 1928 (San Jer6nimo, Peru, 1,000 feet altitude; palmeri Thonaas, 



a synonym). 

 Oryzomys (Oecomys) superans, Sanborn, Publ. Mus. Hist. Nat. "Javier Prado," 



ser. A, Zool., No. 6, p. 21, 1951 (Quincemil, Cuzco, Peru). 

 (Ecomys palmeri Thomas, Ann. Mag. Nat. Hist., ser. 8, vol. 8, p. 251, 1911 (type 



locality, Canelos, Rfo Bobonaza, upper Rio Pastaza, Napo-Pastaza, eastern 



Ecuador; altitude 2,100 feet). 

 (Ecomys nieUeus Anthony, Amer. Mus. Nov., No. 139, p. 4, 1924 (type locality, 



Zamora, Santiago-Zamora, eastern Ecuador, altitude 3,250 feet. — Goodwin, 



Bull. Amer. Mus. Nat. Hist., vol. 102, p. 302, 1953 (type history and measure- 

 ments) . 

 (Ecomys osgoodi Thomas, Ann. Mag. Nat. Hist., ser. 9, vol. 14, p. 287, 1924 (type 



locality, Moyobamba, Amazonas, Peru; altitude about 820 meters above sea 



level); ser. 9, vol. 19, p. 369, 1927 (Yurac Yacu, San Martin, Peru); ser. 9, vol. 



20, p. 601, 1927 (Tingo Maria, Peru, 2,000 feet altitude; measurements). 

 Oecomys osgoodi, Laurie, Ann. Mag. Nat. Hist., ser. 12, vol. 8, p. 276, 1955 (Rfo 



Tigre, Ecuador, 2,000 feet altitude). 

 Oryzomys auriventer, J. A. Allen (not Thomas), Bull. Amer. Mus. Nat. Hist., vol. 



35, p. 118, 1916 (Zamora, Ecuador) [= type series of 0. melleus Anthony]. 



Type: Adult female, skin and skull (BM 11.7.19.12) collected 

 Apr. 28, 1910, by M. G. Palmer. 



Type locality: Canelos, Rio Bobonaza, Napo-Pastaza Province, 

 eastern Ecuador; altitude, 640 meters above sea level. 



Distribution: Base, lower slopes, valleys, and foothills of the 

 Andes drained by the Amazon in Colombia, Ecuador, and Peru, from 

 approximately 200 to 1,200 meters above sea level. 



Characters: Largest and darkest of the subspecies; upperparts 

 and sides tawny, the back evenly mixed or heavily lined with dark 

 brown; underparts gray to buff or ochraceous orange, the dark 

 plumbeous basal portions of the hairs showing through; throat and 

 chest not markedly different from belly. 



Measurements: See table 9. 



Variation: Twenty-five specimens of superans taken during the 

 dry season (January-March) along the upper and middle Rio Caquetd 

 (Florencia; Mecaya; Tres Troncos) vary considerably inter se. A few 

 in prime pelage show either the dark color phase or the bright color 



