Welter — Kinderhook Faunal Studies. 467 



oolite with its peculiar fauna was deposited at Hamburg was 

 essentially contemporaneous with the deposition of the upper- 

 most beds of the Louisiana limestone in the Pike County, 

 Missouri, section. The time of deposition of the Glen Park 

 limestone may have been slightly earlier than that of the Ham- 

 burg oolite, but it may be safely considered to be contempo- 

 raneous with the deposition of some portion of the typical 

 expression of the Louisiana limestone, and doubtless with 

 some portion of the upper half of the formation. 



One of the most striking features of the Glen Park fauna 

 is that its Devonian relationships are more close with the 

 Hamilton fauna than with the Chemung, the latter of which 

 is supposedly a younger fauna than the Hamilton, and one 

 whose position in the standard time scale is placed between 

 the Hamilton and the base of the Mississippian. The explan- 

 ation of this doubtless lies in certain facts connected with 

 the history and migrations of the Hamilton fauna not yet 

 sufficiently well understood. 



On comparing the Glen Park fauna with the older Kinder- 

 hook fauna present in the section at Burlington, Iowa, the 

 fauna characterized by the genus Chonopectus, a notable dif- 

 ference is recognizable. There is not a single species common 

 to the two faunas, and while both exhibit close Devonian re- 

 lationships, the alliance of the Chonopectus fauna is with the 

 Chemung faunas of the New York section, while the alliance 

 of the Glen Park fauna is with the Hamilton as has already 

 been pointed out. Furthermore, the Glen Park fauna also, 

 exhibits, as has been shown, close relationships with the gen- 

 eral Kinderhook fauna of central and southern Missoun, the 

 Chouteau fauna, a fauna which appears in the Burlington sec- 

 tion only in the higher beds of Kinderhook age at that lo- 

 cality, in beds No. 5 and No. 6 of Weller's section.* The 

 lower Kinderhook fauna of Burlington, the Chonopectus 

 fauna, does not occur anywhere in the more southern region 

 occupied by Kinderhook faunas. 



A detailed study of the Kinderhook faunas of the entire 

 Mississippi valley region, shows clearly the dual nature of 



* Trans. Acad. Sci. St. Louis, vol. 10, p. 61. 



