The portrait is of Louis, Dauphin of France (1729–65), father of Louis XVI, Louis XVIII, and Charles X, and is based on a painting of 1767 by Alexandre Roslin (1718–1793).
Signature: Signed in medallion, along right edge, in script: Mme Debon
Inscription: Painted in black in border of medallion at top: Louis Dauphin père du ROI LOUIS XVIII.
Marking: Printed in blue on bottom:  Crossed Ls enclosing fleur-de-lis above Sevres / 1822 (factory mark); painted in black inside foot rim:  I ms. 21; incised beneath mark :  9-61 J; incised inside foot rim:  Li^
Louis XVIII, King of France (after 1824) ; [ Michel Meyer , Paris, until 1993; sold to MMA ]