The ornamental design for a walllath, as shown and described.
FIG. 1 is a top perspective view of a wall lath;
FIG. 2 is a right-side elevation view of the wall lath shown in FIG.
FIG. 3 is a left-side elevation view of the wall lath shown in FIG. 1;
FIG. 4 is a top plan view of the wall lath shown in FIG. 1;
FIG. 5 is a bottom plan view of the wall lath shown in FIG. 1;
FIG. 6 is a front elevation view, enlarged, of the wall lath shown in FIG. 1; and,
FIG. 7 is a rear elevation view, enlarged, of the wall lath shown in FIG. 1.
The wall lath is shown with a symbolic break in its length. The appearance of any portion of the wall lath between the break lines forms no part of the claimed design.