If there’s a single work of art one wishes everyone could see this season, it is Gian Lorenzo Bernini’s Costanza Bonarelli (1636– 1638). A marble bust of the artist’s mistress, it is one of the high points of “Bernini and the Birth of Baroque Portrait Sculpture,” which began a two-city North American tour at the J. Paul Getty Museum in Los Angeles this summer.[1] A fleeting instant captured in stone, it shows the young woman with her head turned and her mouth open, as if about to address someone who has just entered her orbit. Her eyes blaze from the center of a broad, fleshy face, and her chemise has fallen open to reveal part of one breast. Costanza Bonarelli is one of the most psychologically charged and sexually confrontational portraits ever produced—the art historian Howard Hibbard called it “a petrified fragment of passion”—as well as one of the greatest. And if that weren’t reason enough go to see it, Costanza has not left her home in Florence’s Bargello Museum for fifty years, making this North American visit a once-in-a-lifetime opportunity.

As it happens, another portrait bust of a great artist’s inamorata on loan from an overseas museum is on American soil at the same time. Jean-Antoine Houdon’s terracotta Madame Houdon (1786) is included in “Houdon at the Louvre: Masterpieces of the Enlightenment” that was organized by the High Museum in Atlanta.[2] Mme. Houdon bears a striking similarity to Costanza Bonarelli. It, too, captures