MILLER AND REHN : NORTH AMERICAN MAMMALS. 129 



Microtus minor (Merriam) . 



1888. Arvicola austerus minor MERRIAM, Amer. nat., xxn, 



p. 600. July, 1888. 

 1900. Microtus minor BAILEY, North Amer. fauna, no. 17, 



p. 75. June 6, 1900. 

 TYPE LOCALITY. Bottineau, at base of Turtle Mountains, 



Bottineau County, North Dakota. 



Subgenus ORTHRIOMYS Merriam. 



1898. Orthriomys MERRIAM, Proc. biol. soc. Washington, xn, 

 p. 106. April 30, 1898. Type. Microtus umbrosus MERRIAM. 



Microtus umbrosus Merriam. 



1898. Microtus umbrosus MERRIAM, Proc. biol. soc. Wash- 

 ington, xn, p. 107. April 30, 1898. 



TYPE LOCALITY. Mount Zempoaltepec, State of Oaxaca, 

 Mexico. Altitude, 8200 feet. 



Subgenus HERPETOMYS Merriam. 



1898. Herpetomys MERRIAM, Proc. biol. soc. Washington, xn, 

 p. 107. April 30, 1898. Type. Microtus guatemalensis MERRIAM. 



Microtus guatemalensis Merriam. 



1898. Microtus guatemalensis MERRIAM, Proc. biol. soc. 



Washington, xn, p. 108. April 30, 1898. 



TYPE LOCALITY. Todos Santos, State of Huehuetenango, 

 Guatemala. Altitude, 10,000 feet, 



