Marathon, Texas, March 20 - 1924 Thursday Due four days since the beginning of this day, a good representation. The species are all small. Professor Bidden is not at all clear as to the age of these shales. He calls them at first Baptand (= Penn) and later calls them Dolf- camp and counts to place them in the Permian. I may have 25 other species of tivalros, gastriods, hackiords and corals, and all of these are typical Pennsylvanian. The association appears to me to be Cisco. Accordingly all the baptand and dolfcamp due to are Pennsylvanian and the Permian begins with a basal conglomerate, that Bidden sometimes calls his Iters and at other times [illegible] Leonard. In a later publication he does not use Iters. The contact between the Pennsylvanian and Permian is a little more = discordant.