This looks like a likely entry for the marriage of Duncan's parents:
MARGRET MARTIN Marriages: Spouse: DUNCAN MCDOUGALD
Marriage: 02 JUL 1858 Anderston, Glasgow, Lanark, Scotland
And entry in the 1861 Census:
Duncan McDougall 10 Mo, visitor, b. Kilbrandon
Margaret McDougall 24, visitor, b. Stornoway, Rossshire
Malcolm Morrison 22, boarder, Ship Carpenter, b. Stornoway, Rossshire
Flora Munro 34, wife, b. P Kilbrandon, Argyleshire
Peter Munro 46, head, Attendant On Dredgirg (?) Machine, b. P Kilbrandon, Argyleshire
Address: 44 Hill St, Anderston, Glasgow