The ornamental design for a scratchingpost for cats, as shown and described.
FIG. 1 is a perspective view of a scratching post for cats showing my design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is bottom plan view thereof;
FIG. 8 is a perspective view showing the scratching post for cats in use; and,
FIG. 9 is another perspective view showing the scratching post for cats in use.
The broken lines are shown for the purpose of illustrating portions of the scratching post that form no part of the claimed design. The additional broken lines shown in FIG. 8 and FIG. 9 are shown for the purpose of illustrating environmental subject matter that form no part of the claimed design.