branches of branches

The branch that is pictures that can or could be in a square by virtue of being small enough to fit in that square that describes pictures of which some part is in the square branches into pictures whose uppermost and leftmost extents are in the square, or are, at any rate, not above and not to the left of the square, respectively, and pictures whose uppermost and or leftmost extents are above or to the left of the square respectively. The former branch represents pictures which might be in the square while the latter describes pictures which are not in the square.