 The final 50 yen notes were issued from 1951 to 1958, and are known as "B series" notes.An unofficial nickname dubbed "Takahashi notes" are also given for the "B series" as they feature former prime minister Takahashi Korekiyo on the front, and the Bank of Japan building on the back.The first 50 yen coins debuted in 1955, which was the beginning of the end for their 50 yen note counterpart as the two circulated concurrently.