vegetation - eucalyptus trees, crown-of-thorns plant growing - Euphorbia milii (Crown-of-thorns or Christ Plant) is a woody, succulent species of Euphorbia native to Madagascar. The species name commemorates Baron Milius, once governor of Réunion, who introduced the species to France in 1821. It is suspected that the species was introduced to the Middle East in ancient times, and legend associates it with the crown of thorns worn by Jesus.