Keith Edmier’s Penn Station Ciborium (2012-13), the centerpiece of his first solo in New York in five years, is a monumental work that infuses public architectural forms with personal meanings. The domed steel structure studded with cast oyster shells melds references to classical buildings, ecclesiastical structures, industrial-era infrastructure, the seafood restaurant in Grand Central Terminal and the artist’s own studio. The works on view vary widely in form and materials, but they are uniformly dense with allusions. A series of flowers cast in pink dental acrylic and displayed on pink marble pedestals is based on special orchid varieties from a White House garden that are named in honor of First Ladies. The beautiful natural forms become allegories, their significance derived in part from American political culture.