General:
Annual herb from a taproot; stems weak, branched, climbing-sprawling, angled, with short backward-pointing prickles along the angles, 0.3-1.0 m long.
Leaves:
Lower leaves often deciduous, oblanceolate, stalked, 2-10 cm long, to 2.5 cm wide, roughly stiff-hairy and irregularly stiff-fringed, opposite, more or less entire, the others gradually reduced upwards, becoming more elliptic or somewhat diamond-shaped and unstalked, partly whorled or alternate, often widely spaced.
Flowers:
Single or in clusters of 2-3 on short, thick, downward-curving stalks from the axils of leaves or bracts or forks of branches; corollas narrowly bell-shaped; petals at first purplish then blue, fused at base into a short tube that flares (2-3 mm wide) at top to 5 tiny lobes, with 5 white bulges at the throat; calyces with 5 deltoid lobes, each lobe with a tooth on each side near the base; fruiting calyces enlarging (to 1-2 cm wide), becoming compressed, firm-papery, net-veined, prickly with stiff hooked or curved hairs, and forming a 2-lipped covering around the silicles.
Fruits:
Nutlets 4, clustered together, enveloped by the calyx, narrowly egg-shaped, 2.5 mm long, with shiny, cobblestone-patterned surface and small, off-centre groove. vol2_2
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