Opium poppy, Papaver somniferum, showing an unripe seed capsule with a flower in the background. Opium is collected after the petals have fallen, leaving the old stigma (starfish-shaped) & the carpel (capsule), in which the young seeds are contained. The circumference of the capsule is slit (seen here), allowing the milky latex to ooze out. It hardens to form a plastic gummy substance on exposure to air, which is scraped off & formed into balls. Crude opium contains numerous alkaloids including morphine (10%), heroin & codeine. It is used medicinally as a sedative & to relieve pain. It is also used extensively as a narcotic.