128 



General Table of Fossils of the Grand Tower Formation — Continued, 



1 2 3 



*Megnmbonia cf. cardiiformis Hall 



Modiomorpha linguifortnis Hall 



Paracyclas ellipttca Hall x x 



Cf. Pterinopecten multiradiatus Hall x 



Scliicodus sp 



Bellerophon sp 



Bellerophon pelops Hall x x 



Callonema lichas Hall x x 



Euompfwlus decewi Billings x x 



Igoceras conicum Hall (Oriskany) 



Loxonema sp 



Loxonema terebra White 



Murchisonia sp 



Of-thonychia dentalia Hall x x x 



Platyceras blatchleyi Kindle x 



Platyceras carinatum Hall x x x 



* Platyceras dumosum Conrad x 



Platyceras erect um Hall x 



Platyceras subnectum Hall x 



Platyceras thetis Hall x 



Platyostoma lineata Conrad x 



Platyostoma turbinata cochteata Hall x 



Strophostylus zana-ns Hall x x 



Gomphoceras sp 



Gomphoceras sp 



Gyroceras sp • • 



Dalmanites calypso Hall. x 



Dalmanites sp ■ ■ 



Odontocephalus aegeria Hall x x x 



Odontocephalus arermrius Meek (Oriskany?) 



* Phacops cristata Hall (Oriskany) x x x 



Phacops rana Green x 



Proetus clarus Hall x x 



*Pr>oetus crassimarginatus Hall x 



* Proetus cf. folliceps Hall 



* Proetus marginalis Conrad 



* Proetus rowii Green 



* Proetus sp. (Oriskany) 



Onychodus sigmoides Newberry 



Both the Grand Tower formation in Illinois, and the Jef- 

 fersonville beds in Indiana, have been considered a western 

 extension of the Onondaga strata of New York. 



A total of 162 species of fossils were collected from the 

 Grand Tower formation in Illinois, 142 species exclusive of 

 the corals and bryozoa. Kindle lists 158 species from the 

 Jefifersonville beds of Indiana. Out of this almost equal num- 

 ber of species from the respective areas, only 55, or 34 per 

 cent, are common to the strata in the two localities. Of the 

 Grand Tower fossils in the above table, 70 species, or 49 per 

 cent, occur also in the Onondaga beds of New York. The 

 resemblance of the fauna of the Grand Tower formation is 

 thus shown to be closer with that of the Onondaga strata of 

 New York than with that of the Jeffersouville beds of Indi- 

 ana. 



