Henderson's phlox

General:
Taprooted, mat-forming perennial, glandular-hairy throughout.
Leaves:
Leaves crowded, often in threes, 5-10 mm. long and scarcely 1 mm. wide, the margins strongly thickened.
Flowers:
Flowers solitary and sessile at the ends of the stems, often 6-parted; calyx with flat, papery intervals between the herbaceous segments, strongly glandular-hairy, the 5 lobes firm; corolla white, the tube about 1 cm. long, barely longer than the calyx, the 5 lobes about 5 mm. long;.. more