The text of "The Kingdom of the Pearl" is by famed Parisian jeweler, Leonard Rosenthal. He initially published it as a modest pamphlet in 1919, and commisioned Dulac to paint 10 illustrations for a lavish edition published in London the following year. My favorite chapter from the book, reproduced in its entirety: Myths & Legends.
Links to other Edmund Dulac Sites:
The ArtPassions web site has an excellent Dulac page, with many images that I had never seen before: dulac.artpassions.net/dulac.html.