My 'octo' brain has been looking for another, very unusual Schneider Cup racer. Today I found a reference.
Many on this list fly and/or have known Piaggio has been in the airplane business for many years.
The Schneider Cup off water racer I was trying to recall is the Marquette Piaggio c.7.
I believe it is ca, 1929. It rides on 2 small water foils, rather than wheels or pontoons. Besides a forward propeller it has a marine prop aft to get up on plane and clear the prop. I believe the conventional propeller is then engaged to reach flight speed.
I recall the original found its way to the US many years ago and that sometime around the'70's it wound up in CT.
I saw pictures of parts @ the time. It was gloss black. If you search for 'Marquette Piaggio c.7' You will find a radio controlled version flying off water, in Italy, ca. 1988. R3~