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Kola Switch outcrop. Plant collections were made from mudrocks exposed in three vertically successive layers, numbered 1–3 (lower, middle, and upper beds). Sandstone blocks have rolled downhill from the ridgetop, Archer City Formation informal sandstone member 8 of Hentz and Brown (1987). Personnel, l–r: Nicholas Hotton, Sergius Mamay, Louis Todd, Kenneth Craddock
