

562 C. SCHUCHERT PALEOGEOGRAPHY OF NORTH AMERICA 



Diplothema, Crossotlieca, Eremopteris, Palanopteris, Lonchopteris, Mega- 

 lopteris, Lesleya, Neriopteris, Botliodendron, Ulodendron, Lepidoplioros, 

 and WhiUleseya. . . . One-half of these genera scarcely, if at all,, 

 survive the Pottsville. Three or four only outlive the Allegheny. The 

 Westphalian witnessed the maximum development in Sphenopteris, Neu- 

 ropteris, and Aletliopteris, and of the great Lycopod group. It is pre- 

 eminently the stage of the Cycadofllices." 180 



Missourian or Upper Pennsylvania. In the northern Appalachian area 

 the Coal Measures or Missourian series embraces the Allegheny, Cone- 

 maugh, and Monongahela stages. As in the Pottsvillian below, these for- 

 mations rarely have normal marine faunas, and when they are present 

 the variety and abundance never equal that of the western area of the 

 Mississippian sea. The lower half of the Conemaugh has at least three 

 distinctly marine horizons — Brush creek, Pine creek, and the Ames or 

 "crinoidal limestone." In the first or lowest horizon, Eaymond 181 has- 

 found Marginifera wdbasliensis, Astartella vera, Patellostium montfortia- 

 num, Euphemas carbonarius, Bellerophon percarinatus, Trepospira illi- 

 noisensis, Worthenia tabulata, Splicerodoma primagenia, Bulimorpha niti- 

 dula, and EuomphaJus catilloides. Just below the Ames limestone, in 

 "red structureless clay," "at least 725 feet below the Permian (Dunkard 

 series)," he has also found bones of Amphibia and Eeptilia, recently de- 

 scribed by Case (ibid., 1908). These remains pertain to Eryops, the dia- 

 dectid reptile Desmatodon hollandi, and the pelycosaurid reptile Nao- 

 saurus ( ?) raymondi. This discovery is of very great interest, as show- 

 ing that the Permic reptilian fauna was in existence as early as middle 

 Upper Pennsylvanic time. The forms represented appear to be more 

 primitive than those of the Wichita, thought to lie at the base of the 

 Permic. In the northern Appalachian area, the Ames limestone marks 

 the last marine invasion during Pennsylvanic time. The higher lime- 

 stones are without marine fossils, and are regarded as of fresh-water 

 origin, owing to the presence in them of from 2 to 5 coal seams. The 

 fossils are said to be common at times, 182 but of few species, usually 

 Ostracoda, Spirorbis anlhracosia, and Anthracopupa ohioensis ?. 



The Upper Pennsylvanic deposits of the northern Appalachian area 

 are correlated by D. White 183 as follows : 



"I would provisionally place the greater part, if not all, of the Conemaugh 

 together with the Monongahela in the Stephanian. . . . The Stephanian or 



180 D. White: Journal of Geology, vol. 17. 1909, pp. 327-328. 



181 Raymond : Annual Report of the Carnegie Museum, 1909, p. 169. 



182 Hyde : American Journal of Science, vol. 25, 1908. 



183 White : Journal of Geology, vol. 17, 1909, p. 329. 



