Found this googling Sweet Potato ocarina

Sweet Potato Ocarinas were invented in Italy in the 1850s by Giuseppe Donati.

For around 80 years the Sweet Potato Ocarina was made in clay or metal. Picking up in popularity during the 1930's, plastic and wooden Sweet Potato Ocarinas were being made.

What is weird I think I remember getting a plastic one in a stocking one christmas when I was only little. I mean very little like 4 years old. I think it was bright yellow. I seem to want to associate it with a school bus for some reason.