Fur reddish brown above; pale gray beneath: tail one-third the length of the body.
Length of the head and body four inches one line; of the head one inch two lines; of the ears five lines; of the tail one inch three lines and a half. - Obs. These dimensions are rather larger than usual.
Resembles the last species, but is much smaller. Head large; muzzle blunt at the extremity; ears rounded, moderately projecting, relatively longer than in the A. amphibia; incisors white: tail not more than one-third the length of the body, sometimes less. Fur soft and silky, reddish brown mixed with dusky on the upper parts, grayish ash beneath.
Common in meadows, preferring moist situations. Food seeds and roots. Is very prolific; and in certain seasons multiplies to a great extent. Nest constructed of dried grass.