104 The Fauna of the Magnesian Series. 



Besides the above list of fossils Professor Calvin* has de- 

 scribed several species, viz.: 



Metoptoma alta Whitf. 



Tryhlidium sp. 



StraparoUus claytonensis Calvin. 



Straparollvs pristoformis Calvin. 



Raphistoma pepinense Meek. 



Raphistoma multivolvatum Calvin. 



Raphistoma paucivolatutn Calvin. 



Holopea turgid a Hall. 



Murchisonia sp. 



Orthoceras primigenium Vanuxem . 



Cyrtoceras luthei Calvin. 



from the Lower Magnesian of northeastern Iowa. But his 

 descriptions leave us in doubt wheather they are Oneota or 

 Shakopee or both. I could not clearly recognize in the short 

 descriptions, which are not accompanied by figures, any of 

 the species described by me. The Shakopee and Oneota were 

 examined near McGregor, Iowa, and although I found no 

 fossils, still fossils ought to be found there in both forma- 

 tions. These two formations present their normal strati- 

 graphic and lithologic character in Iowa. Fossils from 

 southeastern Minnesota and southwestern Wisconsin, w^hich 

 are on opposite sides of northeastern Iowa, present the same 

 faunas in each of the formations, Shakopee and Oneota. In 

 Iowa they should also occur. Raphistoma multivolvatum 

 Calvin may be R. minnesotense (Owen). His other two spe- 

 cies of Raphistoma one can only reject. His Holopea tur- 

 gida H. ma3^ be H. ohesa Whitf. The others seem to be some 

 that I have not found. 



The Shakopee fauna is most like that of the " Upper Cal- 

 ciferous." That of the Oneota, Jordan and Saint Lawrence 

 is likewise comparable to the Lower Calciferous of New York. 

 It, in fact, resembles the Calciferous far more than it does the 

 peculiar fauna described by Whitfieldtfrom the Baraboo dis- 

 trict of Wisconsin which has been supposed to be " Lower 

 Magnesian." These are: 



•Amer. Geol., vol. 10, pp. 144:148 (1892). 

 fGeol. Wisconsin, vol. iv, p. 194. 



