Fig. 1.

Morphology and flowering stages of Silybum marianum. (a) Morphology of S. marianum plant. Each arrow reflects different flowering stages. (b) Flowering stages of S. marianum. Stage 1: No petals have emerged, and small white seeds are visible near the base of the flower receptacle. Stage 2: Some petals have emerged, and small white seeds are visible near the base of the flower receptacle. Stage 3: Most petals have emerged, but they are not yet withered. Slightly larger white seeds are visible near the flower receptacle. Stage 4: Most petals have emerged, but they are withered. The flower receptacle has thickened, and the seeds are larger and firmer.