470 Trans. Acad. Sci. of St. Louis. 



province, where it occurs in the Hannibal sandstone of north- 

 eastern Missouri and in beds No. 5 and No. 6, comprising the 

 upper ten or twelve feet of the true Kinderhook of the Bur- 

 lington section. The earliest expression of this migration 

 from the southern into the northern province is probably 

 shown in the fauna of the Hamburg oolite. The southern 

 fauna also occurs in the limestone above the Ensflish Eiver 

 grit of Washington County, Iowa, and the Kinderhook lime- 

 stone of Marshall and Tama Counties, Iowa, contains a fauna 

 allied to that of the southern province, although another 

 element is present which is foreign to either of the two faunas 

 under discussion. 



As has already been indicated, the Devonian relationship 

 of the northern Kinderhook fauna is with the Chemung fauna 

 of the east, while the Devonian relationship of the southern 

 fauna is through the Glen Park fauna with the Hamilton of 

 the east. In explanation of these relationships a tentative 

 suggestion may be made, it being recognized that this sug- 

 gestion is based upon evidence as yet insufficiently investi- 

 gated. In the eastern interior sea of later Devonian times, 

 what we call the Chemung fauna, or at least one element in 

 the fauna, is known to have been the invader, it being pre- 

 ceded by the invading " cuboides " and " intumescens " 

 faunas. It is recognized that the resident Hamilton fauna 

 persisted much longer in central and eastern New York than 

 in the western part of the State, the persistent Hamilton 

 fauna of the Ithaca formation being younger than the invad- 

 ing "cuboides" fauna of the Tulley limestone and contempo- 

 raneous with the " intumescens" fauna of the western Port- 

 age formation. It seems not unreasonable to assume as a 

 working hypothesis, that the Hamilton fauna persisted some- 

 where in the eastern interior sea, or in the Atlantic basin, 

 probably in the south, until the close of Devonian time, it 

 being in its later stages contemporaneous with the Chemung 

 fauna further north. The Glen Park fauna and one element 

 of the southern Kinderhook fauna may then be considered to 

 have their origin from this persistent Hamilton fauna, at a 

 time contemporaneous with or even somewhat later than the 



