Algal material has been known to exist in the Pennsylvanian and Lower Permian beds of Kansas for many years. Twenhofel described some in 1919, and later writers have repeatedly mentioned their occurrence. Moore (1935) and Elias (1937) pointed out that they occur quite consistently at certain positions in the depositional cyclothems.
The algae were collected from 74 formations or named formation members which range in age from the top of the Lower Pennsylvanian up almost to the top of the Lower Permian.
The algae described belong mainly to the green and blue-green algae (Chlorophyta and Cyanophyta) and include members of the families Dasycladaceae, Codiaceae, Porostroma and Spongiostroma. The Dasycladaceae are represented by six new species of the genus Epimastopora, the Codiaceae by a new genus Anchicodium represented by six species. Three species of Girvanella are present.
The genera Ottonosia and Osagia named long ago by Twenhofel are discussed, and details of their microstructures are given. The Osagia colonies are shown to consist of an intimate intergrowth of several different algae often associated with Foraminifera belonging to the “Nubecularia.”
Among the Spongiostroma described are the Somphospongia and several species of Cryptozoon.
The importance of the algae as rock builders is considered. Locally they are very important. The relation of the algal deposits to the cyclothems of deposition is noted and discussed.