ADELBERT KELLER, one of the most zealous among the mediaeval romantic antiquaries of the Tubingen school, and well known by his accurate editions of the _Gesta Romanorum, Les Romans des Sept Sages, Romancero del Cid_, and _Gudrun_, has recently, in company with Wilhelm Holland, prepared for the press a new edition of the songs of _Guillem IX., Count of Poictiers and Duke of Aquitania_. In addition to the chair of Professor Extraordinary of Modern Languages, (which our readers need not be informed is nothing very extraordinary at a German university,) Keller holds the far more important office of teacher of the German Language and Literature at the university of Tubingen. We presume that few men, even in France or Germany, have more carefully or enthusiastically hunted over the various MS. libraries of Italy or his own country, in search of Minnesinger and Provencal literature than Keller. * * * * * The twenty-fifth publication of the _Geschichte der Europaischen Staaten_ (History of the States of Europe) consists of continuations of histories of Austria and Prussia. The series is edited by the well-known scholars HEEREN and UKERT. It has been in progress more than twenty years, and is designed to embrace a complete body of American history, by competent authors. Fifty volumes have already been issued, embracing in complete works, Italy, by Leo, finished 1832; German Empire, by Pfister, 1836; Saxony, by Bottiger, 1837; Netherlands, by Van Kampen, 1837; Austria, by Mailath, 1850; France to the Revolution, by Schmidt, 1848; France, from the Revolution, by Wachsmuth, 1844; the Histories of Denmark, by Dahlmann (vol. III. in 1844); of Portugal, by Schafer (vol. III. in 1850); of Russia, continued by Herrmann after Strahl's decease (vol. IV. 1849); of Prussia, by Stenzel (vol. IV. 1850) are all far advanced, and their completion may be looked for at no distant period. Single volumes, also, have appeared, by Zinkeisen, on the Ottoman Kingdom; by Ropel, on Poland; and by Bulau on the Modern History of Germany. The _Athenaeum_ observes that when the series is completed, the Germans and those who read German in other countries will have, in no immoderate compass, a body of European history, uniform in its general plan, and maintaining a standard of competent authorship such as cannot, we believe, be found in any other language. * * * * * The well-known Countess SPAUR, the wife of the Bavarian Ambassador at Rome, is engaged upon a series of memoirs of events connected with the flight of the Pope from Rome in 1849. It will be remembered that the Pope escaped under convoy of the Bavarian ambassador, and the consequent completeness of information added to the graceful elegance of her style, will produce a brilliant and interesting book. * * * * *