an unpretentious opérette in the same year, La Fiancée en loterie, fared no better. After these disappointments Messager finished the 1890s with two considerable successes. Traubner describes Les P'tites Michu (1897) as "a sensational hit", and Harding calls it the best of Messager's opérettes so far (classing Le Basoche as opéra comique, as did its composer). The plot was not strikingly original: critics commented that its story of babies switched at birth was already very familiar from Gilbert and Sullivan operas. Traubner describes the piece as "one of those unusual works that begin well enough and gets better and better". Setting a scene in the market of Les Halles was not innovative, but Messager's chorus for the marchands and marchandes was out of the ordinary, and Traubner also singles out the duet for the Michus in Act 1: "clever, lilting ... pulsating with an elegance and grace that other operetta composers have failed to obtain". He also judges the finales as outstanding, including a waltz number that in other hands would be predictable but is turned by Messager into something much more symphonic. The final work from the decade was Véronique. Messager described it as an opéra comique, but commentators have classed it as a mixture of opérette and opéra comique. The score contains two of the composer's best known numbers, the "Swing duet" ("Poussez, poussez l'escarpolette") and the "Donkey duet" ("De ci, de la"). When the work was revived at the Proms in London in the 1960s, the music critic of The Times commented, "Charming as it can prove in the theatre, the music alone is a little thin, with none of the piquancy that – thanks perhaps to Gilbert – redeems Messager's famous English contemporary Sullivan ... but Véronique has plenty of pretty things". It became and has remained the composer's most performed musical theatre piece. 20th century Messager's work running opera houses in Paris and London limited his composing between Véronique and the period after the First World War. Fortunio (1907) was a rare example in his oeuvre of a sung-through opera. Eight decades later the critic Edward Greenfield described it as "a long-buried jewel of a piece ... an improbable cross between musical comedy and Tristan und Isolde". From 1919 onwards Messager composed no more opéras comiques. Among his post-war stage works, Monsieur Beaucaire, a "romantic operetta" (1919), was his second work to an English libretto.