Henry Stanley (of "Dr. Livingstone I presume" fame) first described the Okapi in his book "In Darkest Africa", which he wrote after exploring the dense Ituri forest of the Congo in 1890. Stanley was somewhat surprised that the Wambutti pygmies he came in contact weren't amazed at his horses, but said they often caught a similar animal in their traps. They called the animal o'api (misinterpreted by Stanley as "atti"). Sir Harry H. Johnston heard rumours of this strange donkey-like animal and led an expedition to find it in 1899. Sir Johnston gained the trust of the Wambutti, and learned from them that the creature was quite like a donkey, but with striped legs. Johnston was quite sure that the O'api was a type of Zebra, and disbelieved the natives when they showed him tracks supposedly made by the animal, as the tracks were those of a cloven-hooved animal rather than the horse-like tracks he was expecting. (Pretty cocky of him, having never laid eyes on an O'api.) Sir Johnston obtained two headbands made from the striped portion of the legs, and sent them back to the Zoological Society of London, where it was determined that the animal was a new species of horse Equus johnstoni . Later a complete skin and two skulls were sent to the society and it was finally determined that the new species was not a horse after all, but a relative of the giraffe.

Okapi are amazing looking animals. They have an incredibly soft velvet-like coat, dark brown to purplish red. The upper legs are striped, with a pattern much like a zebra (hence Sir Johnston's confusion). The lower legs are a snowy white, with black bands at the joints. Okapi have a horse-like head, a thick neck, back legs that are much shorter than the front, and skin covered "knobs" on the head of the males. They truly look like a creature made up of spare parts. They have huge dark colored ears and an obscenely long black tongue. This tongue is so long and flexible that they even clean their ears with it. (Ummm...I guess that's a good thing)

References: http://www.geobop.com/Mammals/Artiodactyla/Giraffidae/Okapia_johnstoni/index.htm
http://www.ultimateungulate.com/okapi.html
http://sandiegozoo.com/postcards/pix/zoo_card-35bc4da052095.jpg
http://gorilla.bio.uniroma1.it/amd/amd146b.html
http://www.colszoo.org/animalareas/aforest/okapi.html
http://animaldiversity.ummz.umich.edu/accounts/okapia/o._johnstoni$narrative.html