extends SE to Clarence Strait, on SW coast of Etolin I., 28 mi. SW of Wrangell, Alex. Arch.
Named in 1879 by W. H. Dall, U.S. Coast and Geodetic Survey (USC&GS), for Alonzo Tyler Mosman, U.S. Coast and Geodetic Survey (USC&GS), who made surveys in Alaska in 1867.
Anita Bay, Burnett Inlet, Cooney Cove, Dewey Anchorage, Jadski Cove, Johnson Cove, Kindergarten Bay, King George Bay, McHenry Anchorage, McHenry Inlet, Mosman Inlet, Quiet Harbor, Rocky Bay, Steamer Bay,
Abraham Islet, Avon Island, Carlton Island, Center Island, Deadman Island, Double Island, Entrance Island, Etolin Island, Etolin Island, Fawn Island, Independence Island, Lincoln Island, Lincoln Rock, Mabel Island, Marsh Island, McHenry Islet, Molver Island, Mosman Island, North Burnett Island, Observation Island, Quartz Rock, Range Island, South Burnett Island, Split Island, Stanhope Island,