Plants biennial, 15 cm to 1 m tall. Root a thick tap-root. Stem glabrous to pilose; hairs white. Leaves compound, 2-3-pinnate, hispid; segments linear to oval; margin deeply toothed; tips mucronate. Peduncles up to 30 cm long, his¬pid. Involucre of pinnately divided bracts, up to 5 cm long; segments filiform to linear. Rays numerous, the outer longer, incurved. Involucel of undivided or divided bractlets; margins entire or ciliate. Calyx teeth minute. Petals white to yellowish or light purple, the outer radiate; the petals of the central flower of an umbel sometimes red. Ovary hispid; styles 0.5 to 1 mm long. Fruit ovoid, 2-3 mm long; primary ridges not prominent, slightly bristly; secondary ridges winged, spiny; spines white; one vitta under each secondary ridge; commissure 2-vittate.