24 D. K. Greger — Devonian of Central Missouri. 



The Cooper limestone in Marion county: Only the 

 eroded, upper beds of the Cooper limestone were exam- 

 ined in this county, notably along See creek, North river, 

 and less extensively along South river. In all the expo- 

 sures studied, the Cooper is covered unconformably by 

 the Saverton shale, which varies in thickness from 3 to 

 45 feet in a distance of less than one mile. Swallow and 

 more recent workers in the county failed to detect the 

 presence of fossils in the formation, but the writer found 

 an abundance of the following species : 



Turbonopsis providencis (Broadhead), Gypidula marionensis 

 sp. nov., Cranmia marionensis sp. nov., Stromatopora sp., Bry- 

 ozoa, 2 species, gen. et sp. indet., Conocardium cooperensis sp. 

 nov. 



Fossils are nowhere so abundant in the Cooper lime- 

 stone as they are in the overlying Callaway and Craghead 

 formations, but careful search in any of its outcrops will 

 bring to light many of its characteristic species, Tur- 

 bonopsis providencis frequently being found on the bed- 

 ding planes of layers that elsewhere seem entirely devoid 

 of fossil remains, and often occurring in colonies of 

 quite large individuals, some of which measure 5 inches in 

 diameter. The genus Martinia is represented by two spe- 

 cies and they are restricted to the Cooper, in fact, the 

 genus is not known to occur elsewhere in the Devonian 

 of Central Missouri. The larger of the two species is 

 not to be distinguished from the Martima glansecerasi 

 (White), of the Otis beds of Iowa, while the smaller, 

 transverse and more abundant form bears a striking re- 

 semblance to M. sublineata (Meek), described from the 

 region of Great Slave lake, British Columbia. 



A complete list of the fossils of the Cooper limestone 

 is given below ; description and illustrations of the fauna 

 will appear elsewhere. 



Bryozoa, 2 species, gen. et sp. indet., Stromatopora sp., Fav- 

 osites sp., Cyathophyllum sp., Spirifer lupusensis sp. nov., 

 Schuchertella altirhynchus sp. nov., Stropheodonta cooperensis 

 sp. nov., CamarotcecMa splicensis sp. nov., Gypidula marionensis 

 sp. nov., Crancena marionensis sp. nov., Martinia sp. cf. glans- 

 cerasi (White), M. sp. cf. sublineata (Meek), Conocardium 

 cooperensis sp. nov., Lunulicardium grande Miner and Gurley, 

 Turbonopsis providencis (Broadhead), Platyceras sp. nov., 

 Loxonema? sp., Gomphoceras sp. 



Fulton, Missouri. 



