PROC. US. NAT. MUS VOL. 110 



HERSHKOVITZ. PLATE 5 



Dorsal aspect (X1 + ) of skull in cert3i\n subspecies oi Oryzomys co7icolor (a-e) a-ndO. bicolor 

 (J-j), showing variation in size with broad overlapping in the opposite extremes of each 

 species, a-c, Oryzomys concolor superans: a, Male (CNHAI 41459), Montalvo, Rio 

 Bobonaza, Ecuador; b, female (CNHM 43257), Rio Pindo Yacu, Ecuador; c, female 

 (CNHM 43252), Yana Rumi, Ecuador, d, e, Oryzomys concolor concolor: d, male (USNM 

 280563), Pueblo Bello, Colombia; e, female (USNlM 280583), El Orinoco, Rio Cesar, 

 Colombia. /, g, i, Oryzomys bicolor bicolor, males: / (CNHM 18541), Holmia, British 

 Guiana; g (UMMZ 80162), i (UxMMZ 80147), both from Llunchi, Rio Napo, Ecuador. 

 h,j, Oryzomys bicolor phaeotis: h, Female (CNHM 84314), Villa Carmen, Cosnipata, Peru; 

 y, male (CNHM 68638), Camante, Marcapata, Peru. 



