Horkelia tridentata Torr. var. illiterata Ertter & Reveal is proposed for aberrant populations clustered in the southeast margin of the species' range in the High North Coast Ranges in California. The variety has most of the diagnostic characters of var. flavescens (Rydb.) Ertter & Reveal, which is otherwise the only variety in the North Coast Ranges, but lacks the hairs on the interior wall of the hypanthium that provide the most reliable distinction between var. flavescens and var. tridentata; the epithet indicates a classic example of plants that “haven't read the book.” This is the only variety of H. tridentata that occurs in and near the Berryessa Snow Mountain National Monument. The relatively few populations indicate that some level of conservation status is warranted.