Description: English: Range of gray-tailed meadow mouse (Microtus canicaudus) and dwarf meadow mouse (Mocrotus nanus nanus) in Oregon. Date: June 1936. Source: The mammals and life zones of Oregonː UNITED STATES DEPARTMENT OF AGRICULTURE BUREAU OF BIOLOGICAL SURVEY
https://archive.org/stream/mammalsandlifezo00bailrich#page/204/mode/2up. Author: Vernon Bailey.