A revision of the honey ants, genus Myrmecocystus, first supplement (Hymenoptera: Formicidae) by Roy. R. Snelling, Bull. Southern California Acad. Sci., 81(2):69-86, 1982. New distribution data are given for ten western species. Two new species are described: M. (Eremnocystus) arenarius is described from all castes; the type locality is Blow Sand Mts., Churchill Co., Nevada. M. (M) christineae is described from all castes from the Ivanpah Mts.. San Bernardino Co., California. New keys to the species of subgenera Eremnocystus and Myrmecocystus s. str. are provided and the two new species are appropriately illustrated.