The ornamental design for a jar with a lid, as shown and described.
FIG. 1 is a top view of the present design;
FIG. 2 is a bottom view thereof; and,
FIG. 3 is a side view, the other three sides being mirror images thereof.
The broken lines showing the pattern on the top and bottom portions of FIG. 3 represent surface ornamentation which does form part of the claimed design.