The ornamental design for a ceiling mounted lightfixture, as shown and described.
FIG. 1 is a front elevational view of a ceiling mounted light fixture
showing my new design, the left side elevational, right side elevational
and rear elevational views being identical thereto;
FIG. 2 is a bottom view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom plan view of a second embodiment of the claimed design;
and,
FIG. 5 is a front elevation view of the second embodiment of the claimed
design, the left side elevational, the right side elevational, and rear
elevational views being identical.