These are the beta elements for Mario Kart 64.
Beta elements Redigera
Kamek was originally intended to be one of the playable characters, but ended up being replaced by Donkey Kong. The Character Select screen was also different, the characters faced the player, and Kamek can be seen in Donkey Kong's space. The working title of this game was Super Mario Kart R. Boos from Banshee Boardwalk had also a different look, the HUD was different from the final version, and item boxes were also completely black with colored question marks on them. The Cape Feather, which was in Super Mario Kart, was also intended to be included, as seen in a certain screenshot of Super Mario Kart R. This particular screenshot can been seen on the back of the packaging of the Nintendo 64 system.
White Mini Bomb Karts were going to appear in Frappe Snowland. However, they was removed in the final version.