=The Typical Italian Opera=.—Thus at the beginning of the 18th century we find the Opera on an overwhelmingly musical basis instead of the oratorical foundation which it had in its inception. Scarlatti fixed its form for a century. He left it consisting principally of recitatives and arias, each opera containing from fifty to sixty of the latter. Aside from these there was but little formal music—only an occasional march or dance besides the overture. The simple recitative was used for ordinary dialogue; hence it was peculiarly applicable to the _Opera Buffa_ (comic opera). The accompanied recitative was reserved for situations of dramatic importance, and the aria served to express individual emotion. The chorus was employed but sparingly, generally appearing only at the end of the act to give greater eclat to the finale. The dance, which in the early Opera had played a part of some importance, was finally banished entirely from the scene, though not from the stage. It was given between the acts as an intermezzo (interlude), and thus developed into the formal ballet. Spectacular features, too, assumed great prominence. =The Intermezzo=.—The Intermezzo has a close connection with the opera. It arose from the custom of introducing something _between the acts_ of a play or opera to entertain the audience during the necessary period of waiting. At first, songs or madrigals were sung, then by degrees the entertainment took on a dramatic form, until at last a drama was given totally independent of the principal play. Singularly enough, the acts of the two plays were performed alternately, neither having any connection with the other. The Intermezzo was always of a gayer, lighter character; thus when the incongruity of the practice became apparent, it naturally evolved into the _Opera Buffa_. This was brought about by the success of the most celebrated comic opera ever written, _La Serva Padrona_ (The Maid as Mistress), by =Giovanni Pergolesi= (1710-1736). This was originally produced (1734) as an Intermezzo between the acts of another play, and afterward made a triumphant progress through all the opera houses in Europe as an independent work.