In the past several years the United States National Museum has received a large number of mammals from central and southern Korea through the auspices of the Commission on Hemorrhagic Fever of the Armed Forces Epidemiological Board. Among these Korean collections are more than a hundred specimens of a murine rodent originally described as " Micromys speciosus peninsulae " by Oldfield Thomas but currently placed in the genus Apodemus . In attempting to ascertain the specific relationships of thi