Bat, Rochester Bestiary, c.1230

The bat, a creature named after dusk (vespĕr), is often seen as despicable for its nocturnal habits and erratic flight patterns at twilight. Unlike other birds, it flies not with wings but with delicate membranes stretched across its arms. Despite being a flying creature, it shares traits with quadrupeds, like having teeth and giving birth to live bat pups. Bats often cling to one another, hanging in clusters that resemble bunches of grapes, showing a rare sympathy among creatures.

They have long been associated with darkness and impurity. Their blood was once believed to cause baldness and in the Leviticus, they are listed among the unclean birds, symbolising those who turn away from spiritual contemplation towards earthly desires. Isaiah warns against such darkness, prophesying a day when people will cast aside their idols to worship moles and bats, representing the rejection of light and truth for false beliefs.

Vespertilio animal ignobilis; a vespere nomen
accepit. eoquod lucem fugiens crepusculo
vespertino. volatibus irrationabilibus et flexuosis
circumvolat. precepti motu acta et non pennis.
set loco pennarum tenuissimis brachiorum mem-
branis suspensa. Est autem volatile. idemque
quadrupes et dentibus utitur. quod in aliis avi-
bus repperire non solet. Animal muribus simile.
non tam voce resonans quam stridore. Parit ut qua-

The bat is a despicable creature: it is named after the dusk, vespĕr, for it runs away from the light and flies erratically and sinuously at evening twilight. Its darting movements are not made by wings but by the delicate membranes of its arms, where wings are supposed to be. It is both a flying creature and a quadruped and has teeth, which is uncommon among other birds. It resembles a mouse and utters screeching sounds. Like quadrupeds,

drupedia non ova; sed pullos; viventes. Habet
et illud hoc vile animal; quod sibi invicem adhe-
rent. et quasi specie botrionis; ex aliquo loco pen-
dent. Et si se ultima queque laxaverit; omnes resol-
vuntur. Quod fit quodam munere caritatis. que
difficile in hominibus huiusmodi reperitur. De qua
dicunt quidam quod si de eius sanguine perun-
gatur capillatus; caluescit. In levitico hec avis inter
inmundas que commedi non debent; reputatur.
Quia contemplativus qui doctrinam quatuor evvan-
gelior ad terrena convertit. utens nocte cupi-
ditatis pro die contemplationis; mitandus non
est. Unde ysaias de tenebrosa doctrina hereti-
corum. qui luci veritatis non appropinquant; dicit.
In die illa proiciet homo ydola auri et argenti
sui; ut adoret talpas et vespertiliones. et cetera.

it does not lay eggs but begets bat pups. These vile creatures also tend to cling to one another; when they are hanging from some place, they resemble a bunch of grapes. If the last one loosens its grip, they all disperse. They do it out of sympathy, which is difficult to find among humans. The blood of a bat will cause baldness when applied to hair. In Leviticus, this creature is enumerated among the unclean birds that should not be eaten, for a contemplative person who turns the teachings of the four Gospels toward earthly things, using the night of lust in place of the day of contemplation, should not be imitated. Hence, Isaiah speaks of the dark doctrines of heretics who do not approach the light of truth. 'On that day, a man will cast away his idols of silver and gold to worship moles and bats'[1].

Further Reading

David Badke, The Bestiary Blog: Animals in the Middle Ages, Bat, November 6 2023, https://bestiary.ca/beasts/beast250.htm

Mynott, J, Birds in the Ancient World (New York: Oxford University Press 2018)

Josh Goldenberg (BA 2012) and Matt Shanahan (BA 2014), Logeion, November 2022, https://logeion.uchicago.edu/

Castiglioni, L. and Mariotti, S. (1996). Vocabolario della Lingua Latina: Latino-Italiano Italiano-Latino. Terza Edizione. Loescher Torino

Curley, M. J., Physiologus: A Medieval Book of Nature Lore (University of Chicago edition 2009)

Rackham, H., M.A., Pliny Natural History Volume III, Libri VIII-XI (London: William Heinemann Ltd, 1949)

Collins, A. H., M.A., Symbolism of Animals and Birds (New York: McBride, Nast & Company, 1913)

Henderson, C., The Book of Barely Imagined Beings (London: University of Chicago Press, 2013)

White, T. H., The Bestiary: A Book of Beasts (New York: G.P Putnam’s Sons, 1960)

Matthews, J. and Matthews C., The Element Encyclopedia of Magical Creatures: The Ultimate A-Z of fantastic beings from myth and magic (London: HarperElement, 2005)

Barney, S. A., Lewis, W. J., Beach A., Berghof O., The Etymologies of Isidore of Seville (New York: Cambridge University Press, 2006)

Endnotes

[1] Isajah NKJV 2:20: In that day a man will cast away his idols of silver and his idols of gold, which they made, each for himself to worship, to the moles and bats,