In 1643 Domenico Panaroli compiled the first "Flora" of an amphitheatre that was first constructed under what emperor?
Domenico Panaroli:  In 1643 he compiled the first "Flora" of the Colosseum, "Plantarum Amphytheatralium Catalogus", where he had noticed many exotic species were naturalized, originally from stowaway seeds that hitch-hiked in bedding straw and in animals' coats, or that had come in more recently, for in the 17th century the Colosseum was full of improvised shelter that housed people and workshops, a den of thieves in the eyes of outsiders (Caneva 2003). Colosseum:  Construction began under the emperor Vespasian in AD 72, and was completed in AD 80 under his successor and heir Titus.
Vespasian