I as well have a Mazzella and Conti in my family tree.
Great Grandfather Giovanni Mazzella and Great Grandmother Mafalda Conti Mazzella.

However I do not know anything from there departure from Ponza, Italy to America. I know they had a son in 1927 born in Pittsburgh, PA (my Grandfather) so they must have arrived sometime in the early 1900s.

This is where my trail ends.
Any help would be great!