Weller — KinderhooJc Faunal Studies. 469 



Kinderhook faunas, is the large, finely striated rhyncho- 

 nelloid shells typically represented by the species originally 

 described as Rhynchonella fffriatocostata, for which the 

 generic name Paraphorhynchus has recently been pro- 

 posed. In the Mississippi valley the genus is known only in 

 the faunas of the northern Kinderhook province, the genus 

 being, indeed, a more characteristic member of the fauna 

 than is Chonopectus which^has such a remarkable local develop- 

 ment at Burlington. Outside of the northern Kinderhook 

 faunas the genus Paraphoriiynchus occurs in beds referred to 

 the Waverly group, near Warren, Pennsylvania, two species 

 being described by Simpson* from that locality as Rhyncho- 

 nella medialis and R. striata, an occurrence which suggests 

 looking for the relationships of the northern Kinderhook 

 faunas in that direction. 



The geographic distribution of the southern Kinderhook 

 fauna is very different from its more northern neighbor, 

 although the two faunas were doubtless in existence contem- 

 poraneously. This fauna has its most typical expression in 

 the Chouteau limestone of central and southwestern Missouri.! 

 The fauna is present in all the beds of Kinderhook age in 

 Arkansas, and occurs with a slightly different expression in 

 the Kinderhook beds of the Mississippi river section south of 

 St. Louis, extending northward to Jersey county and southern 

 Calhoun county, Illinois. It is also the fauna of the Kock- 

 ford, Indiana, goniatite beds, and has been recognized south- 

 ward in Kentucky. 



In the latter part of Kinderhook time communication 

 between the southern and northern provinces was established, 

 and the southern fauna migrated northward into the northern 



* Trans. Am. Phil. Soc.vol. 15, p. 444. 



t In a paper entitled "Correlation of the Kinderhook formations of 

 southwestern Missouri," Jour. Geol., vol. 9, pp. 130-148), the auihor misin- 

 terpreted the Sac limestone described byE. M. Shepard. The fauna given 

 on pages 136-137 of the paper is really the fauna of the;southern extension 

 of the typical Chouteau limestone which overlies the Phelps sandstone with 

 its Ptyctodus fauna. The confusion of this limestone with the Sac limestone 

 was caused by Shepard's failure to sufficiently diflEerentiate it from hia 

 •' Hannibal " shal^ and sandstone, although the bed is a conspicuous one 

 over a wide territory In Green and adjacent counties in Missouri. 



