Lethe was a science fiction fanzine by Jack Riggs.
Lethe was published in Berkeley California, U.S.A. in the 1940s.
Issue #8 appeared in February 1948. Nine issues were published.
Along with Atres Artes, Black Flames, Chanticleer, Guteto, Ichor, Le Zombie, Nova, Shangri L'Affaires, and Voice of the Imagi-Nation,Lethe was included in the anthology fanzine Pacificon Combozine for the 1946 Pacificon Fourth World Science-Fiction Convention.
With fellow fan from the 1940s Louis C. Smith, he released the fanzine Unknown Index in 1946, which was a bibliography and index to the stories and authors featured in Unknown, a pulp magazine that published science fiction, fantasy, and weird fiction.