_Bibliophile Jacob_ LACROIX, we see by the Paris papers, has also discovered a _comedie-ballet_ by Moliere, written in 1654, and never included in any edition of his works. It is entitled _Le Ballet des incompatibies_, and appears to have been written by order of the Prince de Conti, and acted before him by Moliere himself and other persons of the Prince's circle. That it remained so long unknown is explained by the circumstance of a few copies only having been printed for the favored spectators. The plot is described as ingenious, and the verses not unworthy of the author. It is known that when the Prince de Conti presided over the states of Languedoc in 1654, he invited thither Moliere and his company. He professed so much admiration for the actor that he offered him the confidential situation of secretary, which was declined; but it seems natural enough that he should have shown his gratitude by composing one of those entertainments which cost him so little trouble. This Prince de Conti was at one time so passionately fond of theatricals that he made it his occupation to seek out subjects for new plays, but at a later period he wrote a treatise in which theatres were severely condemned on religious grounds, and Moliere himself was personally and violently attacked. * * * * * Among the new biographical works announced in Paris, is one on the Life, Virtues and Labors of the late Right Rev. Dr. FLAGET, Roman Catholic Bishop of Bardstown and Louisville, Kentucky. The author is a clergyman, who accompanied the late Bishop in one of his last missions to Europe. Bishop Flaget died at the age of eighty-seven. * * * * * M. Xavier Marmier, whose visit to the United States we noticed some months ago, has published his _Letters on Canada, the United States, Cuba, and Rio La Plata_, in two volumes--constituting one of the most agreeable works ever published in Paris upon this country. We shall soon, we believe, have occasion to review a translation of the Letters, by a New-Yorker. * * * * * Guizot and Thiers--the most eminent living statesmen of France, as well as her greatest living historians--were for a long time connected with the Paris journals, and each made his first appearance as a writer in criticisms on the Fine Arts. For several years the former published series of articles on the exhibitions of the Louvre, which were remarkable both for artistic knowledge and literary _verve_. The latter also published in 1810 a pamphlet on the exhibition in the Louvre, which excited great sensation--more, however, from its having a political tendency than for its critical importance. * * * * *