Bullet Bill

Bullet Bills are enemies in Mario 64. They appear in Whomp's Fortress, and Dire, Dire Docks in the DS port. They are shot from cannons and will explode upon contact with anything, including Mario, dealing damage.

Torpedo Ted
Some copies reportedly have a variation of Bullet Bills that appear in Dire, Dire Docks. They are found underwater and are fired from cannons by the submarine. Despite resembling the similar Mario enemy known as Torpedo Ted, they are simply referred to as Bullet Bills within the game.