ORYZOMYS. 233 
eastern and southeastern portions; but in Mexico some are met with 
eet elevation, and these forms are provided with a woolly 
covering to protect them from the cold of such high altitudes. 
> 
48. Oryzomys. Rice Rats. 
C. H. Merriam. Synopsis of the Rice Rats (Genus Oryzomys) of the 
United States and Mexico, Proc: Wash. Acad. Scien., 111, 1g01, p. 273. 
Oryzomys Baird, N. Am. Mamm., 1857, p. 458. Type Mus palus- 
No. 7963 Am Mus. Nat. Hist. Coll. Twice nat. s 
