General:
Annual herb from a short, slender taproot; stems slender, ascending, usually much-branched, downy, often becoming glandular above, 8-30 cm tall.

Leaves:
Leaves opposite, egg-shaped to lanceolate, 3-8 mm long, 1.5-4 mm wide, 3- to 5-nerved, needle-pointed, roughly hairy; stipules lacking.

Flowers:
Inflorescence of usually several flowers, borne in typically open, diffuse, leafy-bracted clusters; petals 5, white, narrowly egg-shaped, to 2 mm long; sepals 5, free, narrowly egg-shaped, sharp-pointed, about 3 mm long, hairy.

Fruits:
Capsules egg-shaped to pear-shaped, 3-4 mm long, 6-valved; seeds greyish-purple to black, 0.5 mm long, pimply in concentric rows.

Source:  The Illustrated Flora of British Columbia