PAPERS OX GEOGRAPHY AND GEOLOGY 243 



Maquoketa shale Ft. 



Shale, bluish-gray, in layers 3 to 6 inches thick, alternating with 



calcareous, very fossiliferous bands 10 



Shale, sandy with few fossils 18 



The species of fossils collected from the upper mem- 

 ber of the Maquoketa at this place are listed below. 



LIST OF FOSSILS FROM 1% MILES EAST OF STERLING. ILL. 

 Anolotichia sp. (r) 

 Anaphragma mirabile U. & B. (c"> 

 Batostoma prosseri C. & G. (c) W. L. 

 Batostoma varians i James ) (c) W. L. Wh. 

 Bythopora delicatula ( Nicholson 1 (c) W. L. Wh. 

 Bythopora meeki (James) (c) W. L. Wh. 

 Bythopora striata Ulr. (r-c) A. 

 Dicranopora emacerata iNich.) (r) Richmond 

 Dicranopora fragilis (Bill.) (c) 

 Favositella epidermata (Ulr.) (r) 

 Hallopora subncdosa (Ulr.) (r) Richmond 

 Hallopora cf. subplaaa (Ulr.) (r) 

 Hemiphragma imperfectum (Ulr.) (c) 

 Mesotrypa sp. (r) 

 Nicholsonella sp. (c) 



Rhombotrypa quadrata (Rom.) (c) W. L. Wh. 

 Stomatopora arachnolclea iHall) (c) 

 Dalmanella testudinaria (Dalman) (c) 

 Hebertella inseulpta (Hall) (c) W. 

 Hebertella occidentalis (Hall) (c) Richmond 

 Leptaena unicosata (Meek and Worthen) (c) 

 Platystrophia cumingsi McE. ic> W. 

 Plectambonites sericeus (Sowerby) ic) W. L. 



Plectorthis whitfieldi (Winchell) near P. kankakensis (McC) (c) 

 Rhynchotrema capax (Conrad) (e) 

 Rhynchotrema neenah (Whitfield) (c) 

 Strophomena neglecta (James) tc) W. 

 Strophomena planodorsata Winchell and Schuchert (c) 

 Strophomena planumbona Hall (C) W. L. 

 Byssonychia radiata (Hall) (r) Richmond 

 Bellerophon sp. 

 Cyclonema sp. 

 Tentaculites sterlingensis (M. and W.) (c) 



The species of fossils in the above list clearly repre- 

 sent a fauna that corresponds with that from the upper 

 Maquoketa strata northeast of Scales Mound, and with 

 those found in the Richmond strata along Aux Sable 

 Creek, in the vicinity of Oswego, and at Wilmington. 

 Four of the species do not occur above the WaynesviHe 

 beds in Indiana, and not one of them is restricted to a 

 post-TVaynesville formation in the Richmond of Indiana. 

 On the Mississippi River, at Savanna, Illinois, 30 miles 

 northwest of Sterling, the Upper Maquoketa strata also 

 consist of alternating shale and limestone layers which 

 furnished fossils similar to the species listed from east 

 of Sterling, and certainly represent a corresponding 



