The bonnacon – also known as bonasus; bonacho or vilde kow – is a legendary creature described as a bull with inwardly-curving horns and a horse-like mane.
First described by Pliny the Elder, medieval bestiaries usually depict the bonnacon’s colouring as reddish-brown or black. Due to the fact its ram-like horns were useless for self-defence, the bonnacon was said to expel large amounts of caustic faeces from its anus at its pursuers, burning them and thereby ensuring its escape.
Casius Plinius Secundus, more usually referred to as Pliny the Elder, noted in his Naturalis Historia (“Natural History”), published around the years 77-79 A.D., that the bonnacon could be found in the regions in and around Paonia (modern day Northern Greece) and central Asia. This is far from the only fantastical creature to be found in Pliny’s huge encyclopedia of the natural world, other beings (dog-headed men; basilisks, to name but two), so we can assume not every detail described is exact.
The bonnacon is bull-like in appearance with only the spiralling ram horns and unusual-colouring arousing suspicion. The brown and reddish hues are usually taken as being the tones of its fur, though other accounts tell of it being a hairless beast. Most striking of its attributes are that of its defence: with the horns curving inwards, futile for use against enemies, if had developed a biological defence, the spraying of dung, which was of such a caustic nature that it would feel upon contact with the skin that the afflicted were on fire. What is more, the distance the bonnacon can emit its faeces is reported to be over three furlongs (approaching 2,000 feet).
“There are reports of a wild animal in Paeonia called the bonasus, which has the mane of a horse, but in all other respects resembles a bull; its horns are curved back in such a manner as to be of no use for fighting, and it is said that because of this it saves itself by running away, meanwhile emitting a trail of dung that sometimes covers a distance of as much as three furlongs, contact with which scorches pursuers like a sort of fire.”
So detailed and expansive were Pliny’s only surviving works that they were considered authoritative right up until the Middle Ages and was therefore a common sight in medieval bestiaries of the time, though occasionally the location the bonnacon could be found had moved from Greece to nearer modern day Macedonia. Likewise, over-enthusiastic scholars added fire-breathing to its “arsenal”, perhaps understandable considering the fascination with dragons at the time.
The bonnacon’s horns were said to be huge, shiny black formations, whilst its flesh was meant to be considered quite a delicacy, reason enough for it to receive so much human attention. Alas, there have been no confirmed sightings of bonnacons, though it has featured in the online video game, Final Fantasy XI.