In Carboniferous and Permian Epochs 167 



ferous system; (2) a Middle or Clear Fork Formation, 

 in which, as in the Wichita, fossils are abundant; (3) an 

 uppermost or Double Mountain Formation. The organ- 

 isms in these have been studied by Cope, White, Case, and 

 Hussakof. 



The second of the above named authors also has re- 

 corded a varied list of plants such as Cordaites, Neurop^ 

 teris, Odontopteris^ Pecopteris and Sphenophyllum, that 

 are therefore of Carboniferous affinities. But with them 

 are Gigantopteris, Callipteris, Gomphostrohus, Taeni- 

 opteris and JValchia, that as strikingly suggest a Triassic 

 plant-facies. 



Case has built up an admirable mental "Restoration of 

 the Region and Environment in which the Animals lived" 

 (725:207:147), that deserves quotation in full. He says: 

 "Considering only the region in Texas and Oklahoma, 

 which is typical of all the Red beds, we may restore in 

 imagination a great flat land stretching away from the 

 Wichita Mountains and the Arbuckle Hills to the east 

 and south where it joined the ocean waters. The western 

 border of the flat we do not know. The normally semi- 

 arid conditi^on of the land was interrupted by incursions 

 of the sea, and fluctuations of the climate to more humid 

 conditions. The aridity never attained a degree which 

 prevented the growth of some vegetation, or the presence 

 of pools of water and running streams, but was sufficiently 

 intense at times to prevent the accumulation of much vege- 

 table debris in swamps or stagnant lagoons. In the times 

 of increased humidity, the vegetation increased in quan- 

 tity, the waters accumulated in large areas, and were over- 

 shadowed by a heavy growth, and the streams expanded 

 and spread over their flood-plains, leaving masses of ir- 

 regularly bedded sandstone and clay. . . . Upon this flat, 

 largely around the pools and streams, lived the wonderfully 

 complex amphibian and reptilian life. The waters swarmed 

 with fish and amphibians, and were constantly invaded by 

 predaceous reptiles in search of food. And he sums up 

 by saying: "The fauna was one of estuaries, swamps, 

 lagoons, alluvial plains and open or covered woodlands." 



