The Qilin has, according to some sources, "the body of a deer, the tail of an ox, the hooves of a horse, a body covered with the scales of a fish, and a single horn." That's the origin of the term "Chinese unicorn". However, the Qilin is also often portrayed as having the antlers of a deer - this is a mix-up with the Chinese dragon (long), which does have antlers. See my comment on the picture of the dragon Chiwen in
The Qilin supposedly is a benevolent creature that is only seen during the reign of a benevolent ruler - in the Chunqiu (Spring and Autumn Annals), a Qilin is said to have been captured towards the end of Confucius' life, and Han philosophers later reasoned that this was because Confucius was a benevolent "king without a throne".
The presentation of the giraffe to the court of Zhu Di (Yongle) would have suggested to court ideologists that this was a sign of the emperor's benevolence. It was easy to consider the giraffe to be a Qilin - it does have a head like a deer's, a tail like an ox's, hooves rather like a horse's, a pattern on its body like scales, and two horns (but not one). In fact, some Chinese scholars suggest that the myth of the Qilin arose from a giraffe-like animal that may have once lived in China - perhaps another member of the giraffe family, of which only the giraffe and okapi are left. This bears some similarities to the theory mentioned by Kongmun about the origin of the dragon myth: see
Just like the misleading use of dragon for loong, and phoenix for feng huang, the use of Chinese unicorn for qilin is misleading and leads to misunderstandings concerning Chinese culture. I collect jade carvings and have several qilin carvings, most have horns like a deer, and one has one horn, but none resemble the unicorn. It is very important that this terminology needs to changed.