White Reindeers in the LWW film.

"The reindeer were about the size of Shetland ponies and their hair was so white that even the snow hardly looked white compared with them; their branching horns were gilded and shone like something on fire when the sunrise caught them"
―Chapter 3 [src]

White Reindeer were the creatures that were used to haul the White Witch's sledge. They were driven cruelly by the Witch's dwarf, Ginarrbrik, who used a whip to make them go faster.

These creatures were obviously bred in Narnia, though they never spoke, so it is possible that they were mere dumb beasts instead of talking Narnians.

Nothing else is known about them, and the only other white Reindeer spoken of was the White Stag.