"The Mexican Spiny Pocket Mouse occurs in central and northeastern Mexico and the extreme south of Texas. It inhabits a variety of semi-arid brushy or rocky habitats, and is common where it lives. The ""pockets"" of the pocket Mouse are fur-lined cheek pouches, where seeds are carried from the foraging area to the burrow. Mexican Spiny Pocket Mice are grayish-brown, with white underparts. On the back, a mixture of stiff spiny hairs and soft ones gives the animal a somewhat coarse appearance. These Mice are nocturnal and are active year-round."

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Mammal Species of the World
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