GEOLOGICAL PAPERS 



lOI 



EJ. 



Elk. 



E.J. 



Exi. 



Feet. In. 

 Soft, yellowish, fine-grained impure limestone, ven- shah" 

 and shelly, weathering into thin bands. Pelecj-pods are 

 particularly numerous in this member 4 6 



Cyclofrypa colUna 

 Cydoirypa communis 

 Fistulipora monticulafa 

 Orbignyella monticula 

 Airy pa reticularis 

 Chouctes scitulus 

 Cyrtina umbonaia 

 Pholidostroph ia iowensis 

 Spirifer asper 

 Spirifer euryteines 

 Spirifer ioiceiisis 

 Spirifer subvaricosus 

 Stropheodonta demissa 



Stropheodonta perplaua 

 Platyceras dumosus 

 Actinopteria decussaia 

 Cypricardella bellistriata 

 Goniophora sp. 

 Modiola sp. 



Modiomorpha concentrica 

 Mytilops praecedeiis 

 Myfihrca sp. 

 Paleoneilo cf. plana 

 Paracyclas elliptica 

 Ptychopteria sp. 

 Sphenotus sp. 



Soft, j'ellowish, impure and shaly limestone. Joint planes 

 nearly vertical and close together. Stratification is thin, 

 the rock weathers readily 5 



Cya thop hy Uu m sp. 

 S trial op ora rugosa 

 Spirorbis angulatus 

 Cyclofrypa collina 

 Cyclo tryp a covimun is 

 Cystodictya ham ilto uensis 

 Eridophyllum appressa 

 Euspilopora barrisi 

 FenesteUa vera 

 Fistulipora monticulafa 

 Orbignyella monticula 

 Sem icoscin iu m rhombicum 

 A try pa reticularis 



Chonetes scitulus 

 Crancena iozL'ensis 

 Pholidostrophia ioicensis 

 Roemerella grandis 

 Schizophoria striaiula 

 Spirifer asper 

 Spirifer bimesialis 

 Spirifer euryteines 

 Spirifer iowensis 

 Spirifer subvaricosus 

 Cypricardinia indenta 

 Paleoneilo cf. plana 

 Gomphoceras a fax 



Phacops rana 



Dark-gray to j^ello wish-gray, rather impure limestone, weath- 

 ering rather easily. Jointing characteristically oblique.... 4 



Afrypa spinosa 

 Chonetes scitulus 

 Crancjona iovi'ensis 

 Crauaena romingeri 

 Crania sheldoni 



Cyrtina hamilfonensis, var. recta 

 Cyrtina umbouata 

 Penfamerella dubia 

 Pholidostrophia ioivensis 

 Schizophoria siriatula 

 Spirifer asper 

 Spirifer euryteines 

 Spirifer iowensis 

 Spirifer subvaricosus 

 Stropheodonta demissa 

 Stropheodonta per plana 



Ceratopora sp. 

 Cystiphyllum sp. 

 Strepfelasma rectum 

 Spirorbis angulatus 

 Cyclofrypa collina 

 Cyclofrypa communis 

 Eridotrypa appressa 

 Fistulipora inonticulata 

 Hederella filiformis 

 Orbignyella monticula 

 Pefalofrypa compressa 

 Rhombopora sulcifera 

 Sem icoscin iu m rho mbicu m 

 Ambocoelia unibonata 

 Afrypa hystrix 

 Afrypa reticularia 



Rather soft, gray to yellowish, impure limestone, in rather 

 thick layers which weather easily and show oblique joint- 

 ing 



Strepfelasma rectum Crancena iowensis 



Cyclofrypa communis Crania sheldoni 



Cystodictya hamilfonensis Cyrtina umbonafa 



Cyclofrypa collina Gypidula comis 



FenesteUa vera Penfamerella dubia 



Fistulipora monticulafa Pholidostrophia iowensis 



