Convex closures in planar tetrad lattice

One can take the closure of a set of tetrads in the tetrad plane
instead of taking the closure of the notes of the set in the breed
plane. The results are not always different--the convex closure of the
eight tetrads of the stellated hexany consists of 14 tetrads, leading
to 22 notes; these are the same 22 notes as the convex closure of the
notes in the breed plane.