Lorn,
#1 row 1 is the pollen parent of #2,3,4 in row 3.
#1 in row 3 is the pollen parent of #3 in row 2.
#1 in row 3 is the pollen parent of #1 & 2 row 4.
Note that #1 in row 4 (flat form white with gold center) is the cross of a white with pink center OT x #1 in row 3 (white with red and yellow center).
Most crosses I can trace back, although a few take a while if they go back a ways. If a marker is lost at some point it becomes a bit more difficult.
