M. sylvestris: stem erect, 2-4 feet high; leaves kidney-shaped, with seven deep crenate lobes; stipules lanceolate; flowers large, purple, on axillary aggregated peduncles, the petals much longer than the hairy calyx; fruit-stalks erect, the fruit glabrous. - Waste places. Fl. June to September.
M. rotundifolia: annual; stem decumbent; leaves roundish-heartshaped, with five shallow, acutely-crenate lobes; stipules ovate-acute; flowers small, purple; fruit-stalks decurved, the fruit pubescent. - Waste places. Fl. June to September.