Edward Irenaeus Prime-Stevenson
Born	(1858-01-29)January 29, 1858 Madison, New Jersey
Died	July 23, 1942 (aged 84) Lausanne, Switzerland
Pen name	Xavier Mayne
Occupation	Novelist, journalist
Nationality	American

Edward Irenaeus Prime-Stevenson (January 29, 1858 – July 23, 1942) was an American writer. He used the pseudonym Xavier Mayne.^[1]

Prime-Stevenson (also known as Edward Stevenson, Edward Prime Stevenson, and E. Irenaeus Prime Stevenson) was born in 1858 in Madison, New Jersey,^[1] the youngest of five children born to Paul E. Stevenson and Cornelia Prime. His father was a Presbyterian minister and a school principal; his mother came from a distinguished literary and academic figures.^[1]

After studying law, Stevenson decided to become a writer and a journalist.^[1] During the 1880s, he began a career as a critic in New York City for Harper's Weekly, a political magazine, and as book reviewer and music critic for the weekly Independent. In 1896, Stevenson published The Square of Sevens, and the Parallelogram: An Authoritative Method of Cartomancy with a Prefatory Note by Robert Antrobus that was supposedly written in 1735. However, it is believed that Prime-Stevenson was the author. In 1906, under the pseudonym Xavier Mayne, Stevenson published the homosexually themed novel Imre: A Memorandum, and in 1908 a sexology study, The Intersexes,^[1] a defense of homosexuality from a scientific, legal, historical, and personal perspective.

In 1901, he moved to Europe, living in Florence and Lausanne. He died in Lausanne of a heart attack in 1942, aged 84.^{[citation needed]}

"Between a protozoan and the most perfect development of the mammalia, we trace a succession of dependent intersteps...A trilobite is at one end of Nature's workshop: a Spinoza, a Shakespeare, a Beethoven is at the other... gone on insisting that each specimen of sex in humanity must... follow out two programmes only, or else be thought amiss, imperfect, and degenerate [?] Why have we set up masculinity and femininity as processes that have not perfectly logical and respectable inter-steps?".

— Xavier Mayne, History of Similisexualism^[2]

• Prime-Stevenson, Edward; Trow's Printing and Bookbinding Company (1887), White cockades : an incident of the "forty-five", Charles Scribner's Sons, OCLC 2163459
• Prime-Stevenson, Edward (1891), Left to themselves: being the ordeal of Philip and Gerald , New York, Hunt & Eaton, OCLC 9777119
• Prime-Stevenson, Edward (1906), Imre: A Memorandum, The English Book-Press
• Prime-Stevenson, Edward Irenaeus (1908), The intersexes : a history of similisexualism as a problem in social life 
• Prime-Stevenson, Edward (1913), Her enemy, some friends and other personages, stories and studies mostly of human hearts, G. & R. Obsner, OCLC 458170986
• Prime-Stevenson, Edward (2024), Aan hun lot overgelaten, Carolus den Blanken

Wikisource has original works by or about:
Edward Irenaeus Prime-Stevenson

Wikimedia Commons has media related to Edward Irenaeus Prime-Stevenson.

• Gifford, James J. "Stevenson, Edward Irenaeus Prime-". glbtq.com. Archived from the original on February 4, 2015. Retrieved February 4, 2015.
• Works by Edward Prime-Stevenson at Project Gutenberg
• Works by Edward Irenaeus Prime-Stevenson at LibriVox (public domain audiobooks)
• Works by or about Edward Irenaeus Prime-Stevenson at the Internet Archive
  • Left to Themselves: Being the Ordeal of Philip and Gerald (scanned copy of the novel)