The ornamental design for an eyemask, as shown and described.
FIG. 1 is a top front perspective view of the eyemask, showing our new design;
FIG. 2 is a front elevation view thereof, with the rear elevation view being a mirror image thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a bottom plan view thereof;
FIG. 5 is a right side elevation view thereof, with the left side elevation view being a mirror image thereof; and,
FIG. 6 is another top front perspective view thereof, showing the eyemask in use.
The edges of the eyemask defined by broken lines form no part of the claimed design. The broken line outline of the wearer's head in FIG. 6 assists to portray the eyemask in a position of use and forms no part of the claimed design.