1.The flowers of a cranesbill (Geranium robertianum) during the day at upright stems. 2. The same flowers during the night and in bad weather at bent stems, and with downward-pointing flower openings. 3.,4. Flower of a bellflower (Campanula patula) 5.,6. Flower heads of a scabiosa (Scabiosa lucida). From: A. KERNER von MARILAUN: "Pflanzenleben" ( Plant Lives), 1913