Subject to existing valid claims, the boundaries of the Sequoia National Forest, California, be, and they are, extended to include the following described lands, which shall hereafter be subject to the laws, rules, and regulations relating to said national forest:
Southwest quarter, southwest quarter section 7; section 16 and section 17; east half northeast quarter, southwest quarter, northeast quarter, southeast quarter, northwest quarter, east half southeast quarter section 18; east half northwest quarter, northwest quarter northwest quarter, northeast quarter section 20; northwest quarter northwest quarter section 21; and tract numbered 48 in the southeast quarter section 28, all in township 21 south, range 31 east, of the Mount Diablo meridian in California.