Here are two examples of their treatment of passionate utterance in recitative.

The first is by Peri and the second by Caccini.

Both are settings of the same text in the "Euridice." [Musical Notation: two excerpts] Caccini was somewhat more liberal than Peri in the use of floridity and always showed taste and judgement therein.

Here is a sample of his style taken from a solo by one of the nymphs in "Euridice": [Musical Notation] Caccini also showed that he was not averse to the lascivious allurements of two female voices moving in elementary harmonies.

Here is a passage from a scene between two nymphs upon which rest many hundreds of pages in later Italian operas.
[Musical Notation] This was the immediate predecessor of the well-known "Saliam cantando" in Monteverde's "Orfeo." The innovations of the Florentine reformers included also the invention of thorough bass, or the basso continuo, as the Italians call it.
Ludovico Grossi, called Viadana from the place of his birth, seems to have been the first to use the term basso continuo and on the authority of Praetorius and other writers was long credited with the invention of the thing itself.