The two ERAS referred to in the crossword solution are the Victorian era and the Mesozoic era. The Victorian era was a period of time in the United Kingdom from 1837 to 1901, during which Queen Victoria reigned. It was a period of great industrialization and technological advancement. The Mesozoic era, also known as the Age of Reptiles, was an era that lasted from 252 million to 66 million years ago. During this time, dinosaurs were the dominant species on Earth and the first birds and mammals appeared.