We have this from the University of Nebraska’s Agate Lexicon:
Lemurian Agate, …a new California find, no description, no locality, Trade Name, adv., Pyramid Rock Mart, Lapidary Journal, v. 1, no. 2, p. 79. …adv. Rocks & Minerals, 1947, v. 22, no. 8, p. 746. by Pyramid Rock Mart, Barstow, California. Name also appeared in 1954 catalogue for Gem Exchange (Gem Village), Bayfield, Colorado, p. 3. Fraser and Fraser (1988) listed this material as being named for Lemur, California, a name that does not appear on U. S. Geological Survey Geographic Names Database.
The mystery deepens…