Specifically, for each conformal structure X T(S), pruning X gives a map ML(S)T(S). We show that this map extends to the Thurston compactification of T(S), and that its boundary values are the natural antipodal involution relative to X on the space of projective measured laminations.
We use this result to study Thurston's grafting coordinates on the space of
1 structures on S. For each X T(S), we show that the boundary of the space
P(X) of 1 structures on X in
the compactification of the grafting coordinates is the graph (iX) of the antipodal involution iX : ML(S)ML(S).