Are both A Midsummer Night's Dream and La sonnambula operas?
La sonnambula La sonnambula ("The Sleepwalker") is an opera semiseria in two acts, with music in the "bel canto" tradition by Vincenzo Bellini set to an Italian libretto by Felice Romani, based on a scenario for a "ballet-pantomime" written by Eugène Scribe and choreographed by Jean-Pierre Aumer called "La somnambule, ou L'arrivée d'un nouveau seigneur". The ballet had premiered in Paris in September 1827 at the height of a fashion for stage works incorporating somnambulism.
Achille et Polyxène Achille et Polyxène ("Achilles and Polyxena") is a tragédie lyrique containing a prologue and five acts based on Virgil's "Aeneid" with a French libretto by Jean Galbert de Campistron. The opera's overture and first act were composed by Jean-Baptiste Lully, who died from a conducting injury before he could complete the score. The prologue and the remaining acts are the work of his pupil Pascal Collasse who finished the work, eight months after Lully's death on March 22, 1687. The opera was first performed on November 7, 1687, by the Paris Opera at the Théâtre du Palais-Royal in Paris.