STRATIGRAPHIC POSITION OF BEDS 699 



southern faunal area of the Pleasanton substage of Missouri. 12 In Iowa 

 it is at least not a common fossil in the upper part of the Pleasanton sub- 

 stage near the base of the Hertha limestone, for up to the present there 

 is no record of its existence there in the other counties just east of Mis- 

 souri stage strata. Marginifera muricata is found throughout the Des 

 Moines stage and is especially common in the lower part of the Pleas- 

 anton substage, where it forms bands of limestone in the shale. The 

 presence of these two fossils in the strata close to Adel therefore favors 

 the judgment that the strata at Adel belong well down in the Des Moines 

 stage rather than close to the base of the Hertha limestone, as originally 

 supposed. 13 



12 Hinds and Greene : The stratigraphy of the Pennsylvanian series in Missouri, table, 

 p. 276. Compare also statements on pages 267, 268, 270. and tahle, p. 274. 



13 Formerly it was thought in Iowa that Marginifera (Product us) longispina was as 

 truly an index fossil of the Missouri stage as M. muricata is of the Des Moines stage, 

 but literature with reference to M. longispina (and also of If. wabashensis, a possible 

 synonym) does not support that view. 



Stuart Weller, in Bulletin 153, U. S. Geological Survey, lists Productus muricatus, 

 P. longispinus, and P. wabashensis as three distinct species and P. splendens as a 

 synonym of P. longispinus. 



George H. Girty in his Paleontology of the Pennsylvanian of Missouri (Hinds and 

 Greene, Stratigraphy of the Pennsylvanian series of Missouri, 1915, table, p. 303, and 

 text) lists M. icabashensis as found in Cherokee shales of the Des Moines stage, ? in the 

 Henrietta, and present in all divisions of the Missouri stage excepting the Wabaunsee. 

 He also mentions M. muricata (Chonetes mesolobus, etc.) as restricted to the Des Moines 

 group (stage). Idem, 281. 



In Iowa H. G. Leonard lists P. longispinus as found with P. muricatus and Chonetes 

 mesolobus close to Adel. H. Foster Bain names it as found in the limestone north of 

 Stuart, and Samuel Calvin as found near Logan, in Harrison County. In the last two 

 places it was at the time supposed that the strata were in the Missouri stage. In all 

 three places it is now found that the strata are in the lower part of the Des Moines 

 stage. 



G. L. Smith, in his earliest paper on The paleontology and stratigraphy of the Upper 

 Carboniferous of Iowa (Proceedings of the Iowa Academy of Science, vol. xxii, 1915), 

 names P. muricatus and P. longispinus as both found in the City Bluff shale. In a later 

 paper (idem, vol. xxv, 1918, p. 535) he comments on criticism for identification of M. 

 muricata in the Forbes (Deer Creek) and City Bluff shale, and in the table that follows 

 lists M. wabashensis as a synonym for M. longispina. In his contributions published in 

 1916 (idem, vol. xxiii, p. 87) he had mentioned M. longispina as found near the Nyman 

 coal and AI. icabashensis as found near Thurman. The locations at Thurman, at the 

 Nyman coal, and at the City Bluff beds are all in the Wabaunsee of the Missouri stage, 

 the division from which in Missouri Girty did not report that species. 



F. B. Meek considered both P. splendens and P. wabashensis as synonyms of P. longis- 

 pinus. Final Report of the TJ. S. Geological Survey of Nebraska, etc., 1872, p. 162. 



C. A. White thought both P. muricatus and P. longispinus ranged "through the whole 

 of the Carboniferous or Coal Measure series." U. S. Geological Survey West of the 

 100th Meridian, vol. iv. 1877, pp. 119 and 120. 



G. H. Girty, in his report on The stratigraphy and paleontology of the Upper Carbon- 

 iferous Rocks of the Kansas Section, Bulletin 211 of the U. S. Geological Survey, 1903, 

 lists M. muricata as found not only in Cherokee, Fort Scott, Labette, and Parsons mem- 

 bers of the Des Moines stage, but also in the Deer Creek and Le Compton of the Mis- 

 souri stage. M. wabashensis he reports from twelve different horizons — two in the Des 

 Moines stage, nine in the Missouri stage, and one in the Permian. 



