624 STUART WELLER 



tion, if the outcrop could be traced through the intervening area. 

 This correlation is of especial interest, because it assists in tying 

 together the Kinderhook faunas at Burlington with those of north- 

 eastern Missouri, which are separated by the synclinal folding of the 

 strata which carries the beds far beneath the surface in the area 

 between. 



The presence in the fauna of numerous specimens of Spirifer 

 marionensis, of the typical form occurring so abundantly in the 

 Louisiana Limestone, is another factor of great importance. This 

 species is entirely absent from the Chonopectus fauna at Burlington, 

 nor is it represented by any species at all closely allied to it. In the 

 Burlington section no species of Spirifer likely to be confused with 

 S. marionensis occurs except in the higher beds, Nos. 5 and 6, and 

 this species, although it has usually been identified with S. marionensis, 

 is believed to be a distinct form, which in Missouri occurs only in 

 the Chouteau Limestone or its equivalents, and in beds lying above 

 the Louisiana Limestone. Other species which are common to the 

 Louisiana Limestone fauna and the one under consideration are 

 Chonetes geniculatus and probably Chonetes ornatus, and of these 

 one, C. geniculatus, and perhaps also the other, are recognized in the 

 Chonopectus fauna at Burlington. 



Although the relationships between this fauna from Kinderhook 

 and the Louisiana Limestone fauna are far less striking than between 

 the fauna at Kinderhook and the Chonopectus fauna at Burlington, 

 yet it is believed that they are all but different facies of one fauna, 

 the Louisiana Limestone expression being characteristically the 

 limestone facies, while the Chonopectus fauna at Burlington repre- 

 sents the arenaceous facies. Another point bearing upon the corre- 

 lation is the presence in the Louisiana Limestone of one of the com- 

 monest and most characteristic pelecypod species of the Chonopectus 

 fauna, viz., Grammy sia plena Hall. 1 



In the sections at both Kinderhook and Burlington there is a 

 bed of fine-grained, more or less fragmental limestone, resembling 

 in a marked degree the Louisiana Limestone of Missouri at Hannibal 

 and Louisiana. On the Mississippi River the Louisiana Limestone 



1 A specimen of this species has been seen by the writer in the collection of Pro- 

 fessor R. R. Rowley, of Louisiana, Missouri. 



