For all its conformity to the decorous sartorial requirements of the time, the button-closing front of the bodice is a development of the last half of the eighteenth century. Previously, the overgown did not close over the corset. The part of corset that was left exposed was concealed by an inverted triangle of fabric called the stomacher. Pinned in, it conveyed the impression of an overdress with matching underbodice and petticoat. This gown, like the blue gown, has the innovation of a compiegne, or vest-like stomacher, which is sewn onto the overdress and either pinned or, as in the case of these two gowns, buttoned closed at center front. Typically, the covered boxwood buttons repeat a detail taken from the design of the gown's textile. https://www.metmuseum.org/art/collection/search/99509