RANGE OF CHESTER OSTRACODES 



DISTRIBUTION 



New Design Group 



The following nine genera have been 

 found only in the Renault and Paint Creek 

 formations: Cribroconcha, Hastacyprisj In- 

 cisurella, Tetratylus, Sulcella, Chesterella, 

 OliganisuSj Cyathus, and Coryellina. Four 

 of them, Cribroconcha, Sulcella, Cyathus, 

 and Coryellina, are present in the Pennsyl- 

 vanian, however, and therefore are not re- 

 stricted to the New Design group, and Oli- 

 ganisus is found in the middle Mississippian. 

 The four remaining genera are now known 

 only from the lowest Chester group. 



The following species have been found 

 only in the Renault and Paint Creek for- 

 mations: Cribroconcha costata n. sp., Incis- 

 urella lata n. sp., Glyptopleura bristoli 

 Croneis and Gutke, Discoidella pendens 

 Croneis and Gutke, Oliganisus geisi Croneis 

 and Gutke, and Moorites elongatus n. sp. 

 Of these /. lata and M. elongatus seem to 



be good markers for this group, especially 

 the latter, which is quite distinctive. The 

 only other Chester species of Moorites 

 known is from the Vienna. 



Renault formation. — Of the 31 restricted 

 Renault species, 16 are new. Many of these, 

 together with some of those described by 

 Croneis and Gutke (1939), are too imper- 

 fectly known to serve as good index forms. 

 Few Bairdia are good horizon markers but 



B. aequa n. sp. seems to possess, in its very 

 flat parallel sides, sufficient differentiation 

 to make it fairy easy to recognize. In the 

 Gyptopleuridae, Glyptopleura henbesti Cro- 

 neis and Gutke, Glyptopleurina longuronis 

 n. sp., Glyptopleuroides girtyi and G. per- 

 plexus Croneis and Gutke are distinctive. 

 Hollinella longispina (Jones and Kirkby), 

 from the Carboniferous limestone of Eng- 

 land and Scotland, seems to be confined to 

 the Renault in Illinois. The genus Chester- 

 ella Croneis and Gutke, represented by 



C. exuta and C. fissurata, and C.f incerta 



Correlation of Chester Formations^ 



Group 



Standard 

 Section 



Southwestern 

 Illinois 



Southeastern 



Illinois and 



Western Kentucky 



Southwestern 

 Indiana 



West-Central 

 Kentucky 





Kinkaid fm. 



Kinkaid fm. 



Kinkaid Is. & sh. 



Negli Creek Is. 







Degonia ss. 



Degonia ss. 



Degonia ss. 



Mt. Pleasant ss. 







Clore fm. 



Clore fm. 



Clore sh. & Is. 



Gennet Creek sh. 





Elvira 



Palestine ss. 



Palestine ss. 



Palestine ss. 



Bristow ss. 



Leitchfield fm. 



Menard fm. 



Menard fm. 



Menard Is. & sh. 



Siberia Is. 





Waltersburg ss. 



Baldwin fm. 



Waltersburg ss. 



Wickcliffe ss. 







Vienna fm. 

 Tar Springs ss. 



Vienna Is. & sh. 



Unnamed sh. 







Tar Springs ss. 



Tar Springs ss. 







Glen Dean fm. 



Okaw Is. 



Glen Dean sh.& Is. 



Glen Dean Is. 



Glen Dean Is. 



Horn berg 



Hardinsburg ss. 



Hardinsburg ss. 



Hardinsburg ss. 



Hardinsburg ss. 



Golconda fm. 



Golconda sh. & Is. 



Golconda Is. 



Golconda Is. 





Indian Creek sh. 





Cypress ss. 



Rum a fm. 



Cypress ss. 



Cypress ss. 



Cypress ss. 





Paint Creek fm. 



Paint Creek fm. 



Paint Creek sh.& Is. 



Beech Creek Is. 







Elwren ss. & sh. 





New 

 Design 



Reelsville Is. 





Bethel ss. 



Yankeetown cht. 



Bethel ss. 



Sample ss. & sh. 



Girkin Is. 





Renault fm. 



Renault fm. 



Renault Is. & sh. 



Beaver Bend Is. 







Mooretown sh. & ss. 







Paoli Is. 







Aux Vases ss. 



Aux Vases ss. 









a In part after Weller and Sutton, p. 766, 1940. 



