The ornamental design for a lamp, as shown and described.
FIG. 1 is a top perspective view of a lamp showing my new design as
embodied in a table lamp;
FIG. 2 is a front elevational view thereof, on a reduced scale, the sides
and rear being identical;
FIG. 3 is a bottom plan view thereof on a reduced scale;
FIG. 4 is a top perspective view of my design as embodied in a floor lamp,
it being understood that the embodiment differs from the first only in the
length of the standard which is broken away for convenience of
illustration.