White-eared pocket mice are native to the San Bernardino Mountains and Tehachapi Mountains in California. They are named after there feature of having white or yellowish hair on the external portion of there ear. Within the genus Perognathus, P. alticolus is on the medium to large size. The back of the mouse is yellowish brown with blackish lines and the underbelly of it is white. The tail typically has two or three colors. The under portion is white and the top portion matches the back of the mouse with the tip of the tail being black or ducky in color. The body length, tail length, hind foot length and length of many other feature of the male is much larger than the female. This means they are sexually dimorphic based on size.