The ornamental design for a lavatory, as shown and described.
In a preferred embodiment, the nature of this product is a lavatory for washing human body parts, which is mounted in a room corner.
FIG. 1 is a top, left, front perspective view of a lavatory embodying my new design;
FIG. 2 is a top plan view thereof; and,
FIG. 3 is a front elevational view thereof.
The broken line representations of holes and a drain in FIGS. 1 and 2 and wall environment in FIG. 1 are for the purpose of illustration only, and form no part of the claimed design.