Smithsonian Parterre: Fleur-de-Lis
The greenery is Dwarf English Boxwood--ironically, in my view--an English plant in a French design!
According to another Flickr-poster, the idea of a parterre here at the Smithsonian goes back to 1976 when the museum mounted a huge exhibit next door recalling America's 1876 Centennial Exposition (which was originally in Philadelphia). The remains of the 1876 exposition came to Washington and formed the nucleus of today's U. S. National Museum. Many of the objects are now in the National Museum of American History.
The great financial gift of Enid Haupt allows this garden to be maintained in pristine condition for the free enjoyment of all!