Synaptomys cooperi Baird, 1858 . Mammals, in Repts. Expl. and Surv...., 8(1):558.
TYPE LOCALITY: U.S.A., New Hampshire, Carroll Co., at Jackson .
DISTRIBUTION: Midwestern and E. U.S.A., through S.E. Canada and south to North Carolina and Arkansas; isolated populations in S.W. Kansas and Nebraska.
COMMENT: Subgenus Synaptomys . Revised by Wetzel, 1955, J. Mammal., 36: 120. The subspecies paludis may be extinct; helaletes recently recollected (AVL).
ISIS NUMBER: 5301410008086002001.