I'd never heard of Hans Erni, but his art for the book Man in Society: Patterns of Human Orginization (MacDonald, 1964) really caught my eye when a copy came across my desk the other week. Shades of Picasso, Dali, and (to use a latter-day example) Dave McKean, but still very much his own.
You can learn more about the prolific Erni on his Wikipedia page. He died in 2015, at the rather impressive age of 106!
Here's his contribution to Man in Society.