sentences:  In the late 1960s and early 1970s, Dexamyl spansules—a clear and green capsule containing green and white "beads"—became popular as a street-drug upper nicknamed "Christmas trees", a reference to its appearance.In his autobiography "My Life of Absurdity", Chester Himes writes of his use of Dexamyl in the mid-1950s.He also writes that he stopped taking the drug after his friend Vandi Haygood died from "steady doses of Dexamyl".