Molluscs were obtained from 515 of the 657 grab samples collected 1970–1972 inclusive from southeastern Beaufort Sea, from 29 of the 46 cores taken in the area, and from raised marine deposits at Kay Point and on Herschel Island, Yukon Territory. One hundred and one species have been identified. Water depth was apparently the major factor controlling species distribution. Holocene sea levels, determined by comparing core faunas with the established depth ranges for living specimens, are considered to be reasonably accurate for near-shore sites, but yield excessively shallow water depth figures for deep stations (outer shelf and slope). The anomalous results are probably related to offshore transport of shallow water species.