Osgood's Mouse is a very close relative of the Pinyon Mouse but is larger, and its tail is longer than the head and body. Osgood's Mouse lives in the mountains of southern New Mexico and throughout mountainous central Mexico. Learn more about the Peromyscus gratus, more commonly known as a Osgood's Mouse, in this easy-to-read species overview by the Smithsonian's National Museum of Natural History.