Biennial herb from a fibrous root; stems erect, branched, fleshy, glabrous and glaucous, 30-100 cm tall.
Stem leaves opposite, the pairs arranged at right angles to the adjacent pairs near the stem base, narrowly oblong, 6-12 cm long, 7-15 mm wide, stalkless, broadening in shape upward on the stem; upper leaves distinctly more oval in shape and more or less heart-shaped.
Inflorescence of several stalked involucres solitary in the leaf axils; involucres 3 mm long, purplish; glands 4, with short, rounded horns.
Capsules, 5-10 mm long, globose, coarsely wrinkled; seeds 4-6 mm long, brownish, net-veined.
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
Synonyms and Alternate Names:
Euphorbia lathyrus L. [orthographic variant]
Galarhoeus lathyris (L.) Haw.
Tithymalus lathyris (L.) Hill