The ornamental design for a pen and pencil holder, as shown and described.
FIG. 1 is a perspective view of a pen and pencil holder;
FIG. 2 is a left side elevational view of the pen and pencil holder of FIG. 1, the right side elevational view being a mirror image of the left side elevational view;
FIG. 3 is a front side elevational view of the pen and pencil holder of FIG. 1, the rear side elevational view being a mirror image of the front side elevational view;
FIG. 4 is a top plan view of the pen and pencil holder of FIG. 1; and,
FIG. 5 is a bottom plan view of the pen and pencil holder of FIG. 1.