This article reports the radiocarbon age measurements made at the Lamont Geological Observatory between February 1957 and July 1958. For convenience the sample ages have been classified into the following categories: Table I Geologic Samples—North American glacial geology Table II Geologic Samples—Pluvial lake levels Table III Geologic Samples-Relative sealevel changes Table IV Geologic Samples-Oceanography Table V Geologic Samples-Miscellaneous Table VI Archaeologic Samples Table VII Check Samples Within each table are subdivisions according to geographic origin.