General:
Annual herb from a taproot or fibrous roots; straight, slender, appressed-hairy throughout; stems numerous and prostrate to ascending, or single and erect, to 20 cm long/tall.

Leaves:
Basal leaves virtually absent; stem leaves linear to oblong, entire, 2-6.5 cm long, to 5 mm wide, lower 1-4 pairs opposite, the others alternate.

Flowers:
Inflorescence of terminal, coiled, elongating, loosely-flowered spikes, often with leafy bracts on the lower part; flowers small; petals white, fused at base into a tube that spreads (1-4 mm wide) at top to 5 lobes, with 5 yellow or white bulges at the throat; fruiting calyces 2-4 mm long, ascending-hairy.

Fruits:
Nutlets usually 4, clustered together, egg-shaped or narrowly egg-shaped, 1.5-2 mm long, more or less wrinkled and pimply and sometimes also bristly.

Source:  The Illustrated Flora of British Columbia

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Illustration Source:  The Illustrated Flora of British Columbia