Hermione for a girl, Corky (or Butch) for a boy.
Melissa for a girl. It peaked in 1979, the name remains popular in Mexico, Portugal, and Italy though.
Marius for a guy. In fact, a lot of Roman names could come back. Julius is one of the few roman names to survive this long. Examples of a roman name coming back into use: Darius was never popular until 1991, and remains popular.
Irene also fell out of use in the States after 1920s, with a short rise in 1950. It remains popular in Galicia, Spain, and Italy. Irina is a lovely Balkan form of the name, but never came to the states as far as records go.
My girlfriend's name Irona, though it comes from the Latinized Greek form of Jerome. It hasn't been used very often after the 1900s in her country.
I don't hear Jerome very often either. The name peaked in 1939, started dropping fast after 1989-1990.
I just love onomastics, as much as etymology, name origins, history, and popularity,