I The IxsTErEEXTAi. Coecbbt at Monticello Hall on Monday night was a very fine one. The orchestra was composed of thirteen per formers, and, for its size, we believe that it has not its superior in this country. Among the gems of the occasion were a chorus from Der Tanhaenser, the overture of Lestocq, the overture of Zampa, and a potpourl from the Enchantress, by Mr. Rosenberg, who was the conductor of the orchestra.