The musical forms of the opera seria were modified and remodelled by the comic composers with very unequal skill and success. The recitative needed little transformation; the more trivial treatment of the dialogue suggested itself, and the accompanied recitative was only varied to suit the comic situations. The aria, on the contrary, belonged essentially to musical art, and had been developed at the cost of dramatic truth; opera buffa did not concern itself with either of these facts. It adopted the forms of the opera seria (unless when it parodied them) only in the parts _di mezzo car ottere_ which it had appropriated from the opera seria. {OPERA BUFFA.} (208) The contrasting of different motifs was preserved as an essential condition of musical composition, but the rules as to method and succession were no longer regarded as binding. The subjects were more slender and fugitive, so as to be more easily united, and they profited thereby in freedom of movement and form. In many airs which have only one tempo, the constituent parts of the original aria can be clearly recognised, but the subjects are arranged and repeated according to circumstances, the subordinate subjects are more important and longer, and the means at command are more freely used. Piccinni was the first to introduce the rondo form, which repeats the main subject several times with freely treated intermediate movements. It met with great applause, and was variously developed, being at last adopted in opera seria.[15] But the simpler form of the cavatina was more usual, and received many modifications; the ballad style was also not infrequent. This freedom and many-sidedness of treatment was more especially favourable to the dramatic aspect of the piece, and brought the plot into closer relationship with the music, particularly in the ensembles. Duets, terzets, and quartets were introduced wherever the situation required, and this musical dramatic character reached its highest point in the finales, which are true musical representations of a dramatic climax ascending to a catastrophe. These finales, products of the continual struggle to render music not the ornament but the helpmeet of the drama, are the property of the opera buffa. Nic. Logroscini, who was considered as the inventor of comic opera, and the deity of the _genre bouffon_,[16] is said to have written the first finale, the main subject of which was developed in one continuous movement. Nic. Piccinni (whose "Buona Figliuola" was so well received in Rome in 1761, that it may serve as a date for the recognition of opera {DEVELOPMENT OF OPERA BUFFA.} (209) buffa as a distinct branch of the art) treated each scena of the finale as a separate movement, and displayed far greater variety and more effective working-up.