Dancing, authentic or not, accompanied performances of several French-speaking bands from western and northern Africa. Traditional two-steps and waltzes were in evidence for a concert by Geno Delafose. As a child, Mr. Delafose had followed his father, John, into Zydeco, a syncopated musical form that arose among Louisiana blacks in the 1950s. It was a gumbo of melodies and rhythms adapted from white Cajuns and from Creole and blues sources traceable to people of African descent who'd preceded the Acadiens to Louisiana. Adorned in Stetson, starched shirt, tight jeans, and boots (his day job is ranching near Opelousas), Delafose proved a crowd pleaser.