534 PROCEEDINGS OF THE NATIONAL MUSEUM vol. no 



[Oryzomys (CEcomys)] dryas, Thomas, Ann. Mag. Nat. Hist., ser., 7, vol. 18, 

 p. 455, 1906 ("probably = 6?;coZor"). 



Type: Adult female, skin and skull (BM 99.12.5.4); collected May 

 11, 1899, by R. Miketta. 



Type locality: Paramba, Rio Mira, Imbabura, northwestern 

 Ecuador; altitude, 1,100 meters above sea level. 



Distribution: Known from northwestern Ecuador only. No 

 doubt the range extends northward into western Colombia. Its 

 southward extension may be limited to the Rio Guayas drainage 

 system in Manabi, Bolivar, and Guayas Provinces, Ecuador. Its 

 altitudinal range is from near sea level to about 1,500 meters above on 

 the western slope of the Cordillera Occidental. 



Characters: Size and external characters as in traheatus and 

 typical hicolor: zygomata less expanded; mid transverse width of 

 paired frontals hardly more than greatest width of rostrum and com- 

 paratively less than in other races. 



Measurements: Those of the type of dryas Thomas (from the 

 original description) are followed by those of two adults from Pambilar, 

 Esmeraldas, Ecuador: head and body, 100, 104, 106; tail, 120, 115 

 (dry), 130 (dry); hind foot, 22 {s.u.), 22 (dry, c.u.), 23 (dry, c.u.); 

 ear, 14, 12 [?], 15; greatest length of skull, 27.0. 26.4, 27.4; zygomatic 

 breadth, 15.0, 13.5, 13.4; rostrum, — , 5.1, 5,3; incisive foramina, 

 4.6, 4.6, 4.5; diastema, 7.0, 6.5, 6.4; molar row, 3.8, 4.0 (alveolar), 

 4.1 (alveolar); width of zygomatic plate, — , 2.2, 2.5. 



Remarks: The three near topotypes at hand are brightly colored. 

 One is a juvenal in old pelage but with an irregular patch of bright 

 new adult pelage on nape, back, and left side. 



Specimens examined: Four, from the following localities in 

 Ecuador: Paramba, Imbabura, 1 (BM, type of dryas); Pambilar, 

 Esmeraldas, 3 (USNM). 



Oryzomys bicolor hicolor Tomes 



Hesperomys longicaudatus, Tomes (not Bennett), Proc. Zool. Soc. London (1858), 



p. 548, 1859 (Gualaquiza, Ecuador). 

 Hesperomys bicolor Tomes, Proc. Zool. Soc. London (1860), p. 217, 1860. 

 [Hesperomys] M[yoxomys] bicolor, Tomes, Proc. Zool. Soc. London (1861), p. 



284, 1862. 

 H[esperomys (Rhipidomys)] bicolor, Thomas, Proc. Zool. Soc. London (1884), 



p. 448, 1884 (doubtfully referred to Rhipidomys) . 

 Oryzomys (CEcomys) bicolor, Thomas, Ann. Mag. Nat. Hist., ser. 7, vol. 18, p. 



445, 1906 ("type . . . described from a discoloured specimen with a broken 



tail"). 

 Oryzomys (Oecoviys) bicolor, Sanborn. Journ. Mammal., vol. 30, p. 285, 1949 



(Yarinacocha, Loreto. Peru). 

 CEcomys bicolor, J. A. Allen, Bull. Amer. Mus. Nat. Hist., vol. 35, p. 210, 1916 



(Colombia: Andalucia, Huila; Florencia. Caquetd). — Thomas. Ann. Mag. 



