Lepus cornutus

The lepus cornutus or horned hare is a type of hare or rabbit that in the 16th, 17th and 18th centuries was believed to exist, but is now considered to be fictional.

Horned hares were described in medieval and early Renaissance texts, both as real creatures and as farcical or mythological ones, e.g. by Rabelais in his Gargantua and Pantagruel. But the first mention of the lepus cornutus as described here as a real animal comes from Conrad Gessner in his Historiae animalium, mentioning that they live in Saxony.

Many other scientific works on animals repeated this or similar claims, often with the same depictions. These include John Jonston's "Historiae naturalis de quadrupetibus libri" from 1655, whose illustrations were reused in e.g. the 1718 "Theatrum universale omnium animalium, piscium, avium, quadrupedum, exanguium, aquaticorum, insectorum et angium" by Ruysch.

Gaspar Schott wrote about the horned hare in his 1662 work "Physica curiosa", displaying it on the frontispice and with a further illustration.Gabriel Clauder published in 1687 an article on a horned hare he had sighted, with an illustration. In 1743, Jacob Theodor Klein in his "Summa dubiorum" produced another illustration of the same.

Pierre Joseph Bonnaterre's 1789 Tableau Encyclopedique et Methodique was apparently the last major scientific work to include the lepus cornutus as a real animal. By the late 18th and early 19th century, the idea of a horned hare as a real species was mostly rejected, although e.g. the 1817 "Nouveau dictionnaire d'histoire naturelle" considers it a possibly real but very rare animal.

It has been speculated that the story of the horned hare may not only be caused by fertile imagination or fabrications by taxidermists, but may be caused by sightings of hares with the Shope papilloma virus.

John Jonston, lepus cornutus (middle image), from the "Historiae naturalis de quadrupetibus libri", 1655.

Joris Hoefnagel, Plate XLVII of the "Animalia Qvadrvpedia et Reptilia (Terra)" from ca. 1575

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