The ornamental design for a casementwindow, as shown and described.
FIG. 1 is a front elevational view of my new design;
FIG. 2 is an enlarged fragmentary view of the lower right corner thereof;
and,
FIG. 3 is a cross-sectional view taken generally along line 3--3 of FIG. 1,
the interior surface profile being uniform about the entire perimeter of
the window.