The Jackalope is well known to cryptozoologists, but it is generally admitted it is a fictitious beast. It is a hare with antlers growing from its head. Some suspect it was invented by a man named Douglas Herrick in quite modern times. He was supposed to have made a Jackalope by taxidermy in 1934.
However, such creatures were also the object of belief in Germany. Conrad Gesner, the 15th Century zoologist, believed in it, as did the French zoologist Buffon. In Germany the horned hare was called a Raurackl or Wolpertinger. The Germans also believed in a horned rabbit called a Rasselbock. How come the same creature flourished in the lore of both countries?
The answer may be quite simple. There is a disease to which hares are susceptible called Shope papilloma, which causes antler-like tumors to grow on the head. In this we may have the origin of the belief on both sides of the Atlantic.