They are joined in the last four by Bass, Dunbar and Gullane, the latter having defeated holders Haddington in the quarter-finals yesterday.
In Alan Smith/Scott Walker and Stuart Menzies/Fraser Syme, Gullane are represented by a strong quartet but they faced a tough test against an equally-impressive Dunbar side.
First round: Winterfield bt Gullane Comrades 9 and 7; Haddington bt Rhodes 3 and 2; Whitekirk bt Gullane 9 one hole; North Berwick bt The Honourable Company of Edinburgh Golfers7 and 6; Dirleton Castle bt Aberlady 12 and 11; Dunbar bt Gifford 2 and 1; Glen w/o Dunbar Castle scr. Second round: Bass Rock bt Longniddry 6 and 4; Luffness New bt Kilspindie 6 and 5; Royal Musselburgh bt Thorntree 5 and 4; Tantallon bt Musselburgh 4 and 3; Gullane bt Winterfield 5 and 3; Haddington bt Whitekirk 3 and 2; Dirleton Castle bt North Berwick one hole; Dunbar bt The Glen 4 and 3. Quarter-finals: Bass Rock bt Luffness New 2 and 1; Royal Musselburgh bt Tantallon 4 and 2; Gullane bt Haddington 6 and 5; Dunbar bt Dirleton Castle 5 and 3.