Euphorbia: named for Euphorbus, Greek physician of Juba II, King of Mauretania. Juba was educated in Rome and married the daughter of Antony and Cleopatra. He had written about an African cactus-like plant he knew about from the slopes of Mt. Atlas which was used as a powerful laxative. That plant may have been Euphorbia resinifera, and like all Euphorbias had a latexy exudate. Euphorbus had a brother named Antonius Musa who was the physician to Augustus Caesar in Rome. When Juba heard that Caesar had honored his physician with a statue, he decided to honor his own physician by naming the plant he had written about after him. The word Euphorbus derives from eu, "good," and phorbe, "pasture or fodder," thus giving euphorbos the meaning "well fed." Some sources suggest that Juba was amused by the play upon words and chose his physician's name for the plant because of its succulent nature and because of Euphorbus' corpulent physique.
[Cal-IPC] Ecological effect: Euphorbia oblongata (oblong spurge) is a perennial forb/herb (family Euphorbiaceae) found sporadically in California. This plant may be toxic to humans. It is inedible to wildlife and inhibits the growth of surrounding plants. (link added by Mary Ann Machi)