CHESTER CORRELATIONS 



13 



to 27. While the Reynolds fauna is small, 

 those species found in it are quite distinctive. 

 The present study shows a decided preva- 

 lence of Elvira species, all but one of the 

 restricted species occurring in this group. 

 Within the group there is a dominance of 

 Menard forms. The overlying Talcott and 

 Ada members are probably also referable to 

 the Menard, and the Droop may be equiva- 

 lent to the Palestine as they correspond lith- 

 ologically more closely than do the shaly 

 Webster Springs and Bickett members. 



The upper Chester age of the Reynolds is 

 shown by the presence of Ectodemites mono- 

 mastadis, Deloia serrata and large numbers 

 of Carboprimitia, among which is found 

 C. depressa Croneis and Funkhouser. The 

 correlation of the Reynolds with the Me- 

 nard, which is high in the type Chester 

 series, raises an interesting speculation as 

 to the West Virginia equivalents of the 

 Clore and Kinkaid, and as to the probable 

 age of the many hundreds of feet of Mauch 

 Chunk beds which must lie above the 

 equivalent of the highest Chester formation 

 of the Illinois basin. 



Fay etteville shale. — Simonds (1891) de- 

 scribed this formation from outcrops in 

 northwestern Arkansas, but confused it with 

 the Moorefield. Adams and Ulrich (1904) 

 gave the correct position of the formation 

 in the succession and later (1905) the same 

 authors placed the Wedington sandstone 

 in the upper Fayetteville as a member of 

 that formation. Croneis (1930, p. 69), 

 after an exhaustive faunal study, concluded 

 that "although these Arkansan beds may be 

 correlated with parts of the Chester series 

 of Illinois, they are more closely related to 

 such southern formations as the Caney shale 

 of Oklahoma and the upper Gasper, Gol- 

 conda and Bangor formations of Alabama". 



David White ( 1937 ) , from a study of the 

 fossil plants, determined the age of the 

 Wedington sandstone as upper Chester. 

 Girty (1910) described, but did not figure, 

 13 new species of ostracodes from the Fay- 

 etteville of Arkansas. Later, Harlton 

 (1929) described 12 species, most of which 

 were new, from the formation in Arkansas 

 and Oklahoma. However, neither Girty 

 nor Harlton attempted correlations with 

 type Chester formations. Half of their 

 species have not been recognized in the Illi- 

 nois Chester, largely because of the lack of 

 illustrations in the former paper. How- 



ever, an examination of some of Girty's 

 types has overcome a part of this difficulty. 

 Our collections contain about 50 species 

 from Oklahoma and Arkansas and, eliminat- 

 ing new species and duplicates, there remain 

 about 30 species on which correlations can 

 be based. 



There appears to be close agreement in 

 the distribution of the Oklahoma and Ar- 

 kansas species with respect to the type 

 Chester, each showing two distinct affini- 

 ties, one with the middle Chester (Golcon- 

 da) and the other with the upper Chester 

 (Clore and Kinkaid). The restricted Ches- 

 ter species show that the affinity of the 

 Fayetteville is much closer with the upper 

 Chester than with the Golconda. This cor- 

 relation is in close agreement with the con- 

 clusions of Croneis based on the megafauna, 

 because the Bangor limestone occurs below 

 the Pennington shale. The latter, according 

 to Reger (1926, pp. 311-312) is equivalent 

 to the Hinton and succeeding groups, which 

 may be younger than any formations in the 

 type Chester section. Thus the Bangor of 

 Alabama and Tennessee, the Fayetteville 

 of northeastern Oklahoma and Arkansas, 

 and equivalent portions of the Caney shale 

 of Oklahoma appear to correspond to the 

 Elvira group of Illinois. 



The Elvira species occurring in the Fay- 

 etteville are as follows, the particularly 

 significant ones being starred. 



Bairdia aculeata n. sp. 



Bythocypris clorensis Croneis and Funk- 

 houser 



Healdia fayettevillensis Harlton 



Healdia vinitaensis Harlton 

 *Glyptopleura inoptina Girty 



Glyptopleura multicostata Morey 

 *Amphissites rugosus Girty 

 *Denisonia cincta Croneis and Bristol 



Lochriella reversa (Morey) 



Sansabella harrisi Croneis and Funkhouser 



The most characteristic Fayetteville spe- 

 cies, GraphiadactylUs arkansana (Girty), 

 which outnumbers all others in most of the 

 Oklahoma and Arkansas collections, is not 

 represented by a single specimen in the 

 Chester collection of Illinois and adjacent 

 states that have been studied. Other species 

 of GraphiadactylUs are known from the 

 lower Mississippian (Kinderhook) of south- 

 ern Illinois but these are easily differenti- 

 ated from the Fayetteville species. 



