I02 



ILLINOIS ACADEMY OF SCIENCE. 



Eih. 



Elf. 



Eie. 



Hemitrypa fenera 

 Orbignyella monticula 

 Sem icoscin in m rh ombicuin 

 Spirorbis sp. 

 Athyris fiiltonensis 

 A try pa hystrix 

 Airy pa reticularis 

 Chonetes scitulns 



ProducteUa subalata 

 Reticiilaria fimbriata 

 Schizoplioria striatula 

 Spirifer as per 



Spirifer iozvensis 

 Spirifer euryteines 

 Spirifer snbvaricosus 

 Stropheodonta demissa 



Feet. In. 



Stropheodonta perplana 



Gray, thinly-bedded, rather impure hmestone, weathering 



easily. Fossils rather numerous 2 6 



Ceratopora sp. 

 Streptelasma rectum 

 Cyclotrypa communis 

 Cystodictya ha)niItonensis 

 Eridofrypa appressa 

 Euspilopora barrisi 

 Fistulipora monticulata 

 Hemitrypa tenera 

 Orbignyella monticula 

 Petalotrypa compressa 

 Rhombopora subannulata 

 Semicoscinium rlwmbicum 

 A try pa hystrix 

 Atrypa reticularis 

 Chonetes scitulus 



Crcmcena iozvensis 

 Cyrtina umbonata 

 Pentamerella dubia 

 Schizophoria striatula 

 ProducteUa subalata 

 Reticularia fimbriata 

 Spirifer asper 

 Spirifer bimesialis 

 Spirifer euryteines 

 Spirifer iozvensis 

 Spirifer subvaricosus 

 Stropheodonta demissa 

 Stropheodonta perplana 

 Tentaculites bellnliis 

 Pliacops rana 



Eig. Gray, fine-grained, easily-eroded, impure limestone, shaly in 



places. Fossils not numerous but varied 2 



Streptelasma rectum 

 Cyclotrypa communis 

 Cystodictya hamiltonensis 

 Fenestella vera 

 Fistulipora monticulata 

 Hemitrypa tenera 

 Orbignyella monticula 

 Semicoscinium rhombicum 

 Athyris fultonensis 

 Atrypa hystrix 

 Atrypa reticularis 



Stropheodonta perplana 



Chonetes scitulus 

 Crania sheldoni 

 Lingulodiscina marginalis 

 Pholidostrophia iowensis 

 ProducteUa subalata 

 Reticularia fimbriata 

 Schizophoria striatula 

 Schuchertella chemungensis 

 Spirifer subvaricosus 

 Spirifer iozvensis 

 Stropheodonta demissa 



Yellowish, impure, richly foss 

 Streptelasma rectum 

 Cyclotrypa communis 

 Cystodictya hamiltonensis 

 Fenistella vera 

 Fenestropora occidentalis 

 Hemitrypa tenera 

 Orbignyella monticula 

 Rhombopora subannulata 

 Semicoscinium rhombicum 

 Atrypa hystrix 

 Atrypa reticularis 



iliferous limestone 



Chonetes scitulus 

 Cyrtina umbonata 

 Schizophoria striatula 

 Schuchertella chemungensis 

 Spirifer iozvensis 



Spirifer snbz'aricosus 



Stropheodonta demissa 

 Stropheodonta perplana 

 Bellcrophon pelops 

 Actinopteria decussata 

 Phacops rana 



Layer of hard, dark gray limestone 



Stylodictyon expansum Schizophoria striatula 



Atrypa hystrix Spirifer bimesialis 



Atrypa reticularis Spirifer euryteines 



Cyrtina hamiltonensis Spirifer subvaricosus 



Pholidostrophia iozvensis Stropheodonta demissa 



