“Sculptural Group of a Seated Poet and Sirens,” Greek, 350–300 BC; terra cotta with ploychromy, also known as “Orpheus and the Sirens.” The J. Paul Getty Museum is returning its Orpheus group of sculptures — a culturally significant group of nearly life-size terra-cotta figures known as “Orpheus and the Sirens,” some of the museum’s greatest antiquities — to Italy. The …