Artists, who have played with their own pareidolia first, know how to play with the pareidolia of the beholders of their works.
I incidentally found this in December 2017 as bycatch from my Snark hunt:

2017-12-23
Götz Kluge's blog about Lewis Carroll and Henry Holiday's tragicomedy
The Butcher reasoning with the Beaver.This is the illustration (partially inspired by various works of other artists) to the chapter The Beaver’s Lesson.
Images:
2017-09-26, updated: 2022-09-04

Monsters, by Henry Holiday (left) and J. J. Grandville (right).
[…] One of the first three [illustrations] I had to do was the disappearance of the Baker, and I not unnaturally invented a Boojum. Mr. Dodgson wrote that it was a delightful monster, but that it was inadmissible. All his descriptions of the Boojum were quite unimaginable, and he wanted the creature to remain so. I assented, of course, though reluctant to dismiss what I am still confident is an accurate representation. I hope that some future Darwin in a new Beagle will find the beast, or its remains; if he does, I know he will confirm my drawing. […]
(Henry Holiday (1898): The Snark’s Significance)
Once you meet the Boojum, you might be Going Slightly Mad.

The big beast perhaps gave birth to a Boojum.
(John Tufail made me aware of this illustration by J. J. Grandville.)