82 BBACHIOPODS. 



Spirifera rostellata HALL. 

 Spirifer rostellatus Hall, 1858: Geology Iowa, vol. I, p. 641, pi. xx, 



figs. 2a-c. 



Of the 8. grimesi type, but very much smaller. 



Horizon and localities. Lower Carboniferous, Keokuk 

 limestone : Bonaparte ( Iowa ). 



Spirifera pseudolineata HALL. 

 Spirifer pseudolineatus Hall, 1858: Geology Iowa, vol. I, p. 645, pi. xx, fig. 4. 



Like 8. lineatoides but broader, smaller, with mesial fold 

 more pronounced, and ornamentation finer. 



Horizon and localities. Lower Carboniferous, Keokuk 

 limestone : St. Francisville ( Clark county ). 



Spirifera leidyi NORWOOD & PRATTEN. 

 Spirifer leidyi Norwood & Pratten, 1855: Jour. Acad. Nat. Sci., Phila., 



(2), vol. Ill, p. 72. 

 Spirifer leidyi, var. chesterensis Swallow, 1866: Trans. St. Louis Acad. 



Sci., vol. II, p. 409. 

 Spirifer leidyi, var. merimacensis Swallow, 1866: Trans. St. Louis Acad. 



Sci , vol. II, p. 410. 



Shell similar to that of 8. keokuk. 



Horizon and localities. Lower Carboniferous, Kaskaskia 

 limestone : Ste. Mary ( Ste. Genevieve county ) ; Saint Louis 

 limestone : Ste. Genevieve. 



Spirifera increbescens HALL. 



Spirijer increbescens Hall, 1858: Geology Iowa, vol. I, p. 706, pi. xxvii, 



figs. 6a-i. 

 Spirifer increbescens, var. americanus Swallow, 1866: Trans. St. Louis 



Acad. Sci., vol. II, p. 410. 



Very closely related to 8. keokuk and may eventually prove 

 identical with that species. 



Horizon and localities. Lower Carboniferous, Kaskaskia 

 limestone: Ste. Mary ( Ste. Genevieve county). 



