BASAL MEMBER 53 



ures down as far as the Hudson River shales, to what prac- 

 tically is now known as the Lower Carboniferous or Missis- 

 sippiau series. The Louisiana or Lithographic limestone was 

 not included ; for his "Argillaceous Martites" seem to have been 

 regarded as the basal member. Swallow,* Hallf and White,f 

 who were well acquainted with the section and its fossils, cor- 

 related the beds immediately below the Burlington limestone 

 with the Chemung ( Devonian). In northeastern Missouri and 

 adjoining portions of Iowa and Illinois, the "Chemung" in- 

 cluded the Chouteau limestone, Vermicular shales and Lith- 

 ographic limestone. Hall, who had studied more particularly 

 in Iowa, erroneously regarded certain sandy shales or yellow 

 sandstones, just below the great limestone at Burlington, iden- 

 tical in age with a lithologically similar rock 50 miles to the 

 northward, at the mouth of Pine creek, in Muscatine county, 

 Iowa. Tbe latter, as has been stated, has recently been 

 shown by Calvin || to belong to the Hamilton group, as known 

 in Iowa. Consequently Hall, having investigated the more 

 northern locality more thoroughly perhaps, very naturally came 

 to the conclusion that the entire formation under considera- 

 tion as he understood it was actually Devonian. But as 

 already shown, the rocks of the two localities are widely sep- 

 arated in point of time. 



Meek and Worthen, § who had considered chiefly the fossils 

 in the upper part of the so-called " Chemung," both at Burling- 

 ton, Iowa, and Kinderhook, Illinois, a few miles from Hanni- 

 bal, Missouri, regarded the fauna to be more closely related to , 

 the Carboniferous than to the Devonian. Since the publica- 

 tion of these views, writers upon the subject have accepted 

 them, and they have been adopted in the geological reports of 

 Illinois, Missouri and Iowa. 



By reference to the vertical section already given, it will 

 be seen that the commonly known Kinderhook of this region 



*Geol. Sar. Missouri, Ann Eep , p. 101, 1855. 



tGeol. Iowa, Vol. I, p. 99, 1838. 



JProc. Boston Soc. Nat. His., Vol. XIII, p. 289, 1862. 



II Am. Geologist, Vol. II, p. 25, 1889. 



§ Am. Jonr. Sci . , (2) , Vol. XXXII, p.- 167. 1866. 



