Monsters from the Id consists of two short stories by Clark Ashton Smith that demonstrate, brilliantly, the link between poetry and horror, which is that both have their roots in the unconscious.
The Seed from the Sepulcher is remarkable as an evocation of the horrific so intense that at a public reading, performed at a Mensa gathering some years ago, there were literally gasps from the audience at the climax. I have never read a tale of more effective horror-- it is so lucid and so well-realized that it fascinates, like an adder. It is completely unforgettable. And, all the more astonishing, it achieves its effect without monsters, mayhem, significant violence or blood, relying instead upon the full development and visualization of its imaginative concept; in other words, upon an idea. The ending is, poetically, perfect.
The Double Shadow demonstrates even more clearly the poetic link. Smith had little formal schooling, but read widely in the classics, including Greek and Roman mythology, and apparently at an early age read the unabridged Oxford English Dictionary from cover-to-cover. Epic richness is the result, his best works studded with rare and costly words like fatal gemstones in the crown of some baleful king. His prose in this piece is a poetry, glinting darknesses from the depths moving in mesmeric rhythms. It is art of a high order, surely the equal of Poe's, and a worthy study for any of the poetically inclined who want to explore poetry's tendrils into the unconcious mind.
For the adventurous, here are the links. Both stories are short, perhaps ten to fifteen pages. I'd be most interested in hearing from anyone who essays to read them.
The Seed from the Sepulcher, by Clark Ashton Smith.
The Double Shadow, by Clark Ashton Smith.
The Douglas-Ouyang Planets ...an artistic speculation. Um, what? That's Cordwainer Smith? Oh. That's very different! Never mind...