I claim the ornamental design for a dolly, as shown and described.
FIG. 1 is a front perspective view of a dolly embodying the novel design;
FIG. 2 is a top plan view of the dolly of FIG. 1;
FIG. 3 is a bottom plan view of the dolly of FIG. 1;
FIG. 4 is a side elevational view of the dolly of FIG. 1, the other side and the front and rear elevational views being the same;
FIG. 5 is a bottom perspective view of the dolly embodying the design;
FIG. 6 is a top plan view of an alternate embodiment to the one shown in FIGS. 1-5 but showing three projecting legs instead of four about the periphery of the dolly;
FIG. 7 is similar to FIG. 6 but showing six projecting legs; and,
FIG. 8 is similar to FIGS. 6 and 7 but showing five projecting legs.
The broken lines shown in FIGS. 6-8 are to show the boundaries of the claimed design.