306 STUART WELTER 



several other local formations, and as the relationship between 

 the faunas of these formations had previously been recognized, 

 and the name Kinderhook applied to them all, it seems best to 

 use the latter name instead of Chouteau for the first epoch. 



In order to have a right understanding of the history of the 

 continental interior during Mississippian time, it will be neces- 

 sary to glance briefly at the events immediately preceding 

 During the greater part of Devonian time, the eastern interior 

 region of North America was occupied by the great Mediter- 

 ranean Appalachian sea. This sea extended from the Lauren- 

 tian land on the north to the western extension of the Appa- 

 lachian land 1 on the south, and from the Appalachian on the east 

 to the Missouri land on the west. The outlines of this sea were 

 continually changing during Devonian time, and at intervals it 

 was joined by open passages in different directions with the 

 outer oceans. Near the close of the Hamilton epoch, a passage 

 through the northwestern portion of North America was opened, 

 by means of which communication was established between the 

 Appalachian sea, and the Eurasian ocean. This northwest pas- 

 sage crossed northern Missouri, Iowa, and southwestern Min- 

 nesota, and extended northward through Manitoba and the 

 Mackenzie Valley. The Chemung fauna of the Appalachian 

 province contains an important element derived from the Euro- 

 pean faunas, an element which without doubt found its way 

 into the Appalachian sea through this northwest passage. 



Just before the opening of Mississippian time, the distribu- 

 tion of land and water in North America was about as indicated 

 in Fig. A, the northwest passage being connected with the 

 Eurasian province. The progress of events during the period 

 was, first, an epoch of disturbance, of readjustment and sinking 

 land; second, a long epoch of quiet and equilibrium, with wide- 

 spread marine conditions ; and third, another epoch of disturbance 

 with further readjustment between the interior province and its 

 neighbors. These three epochs are : the Kinderhook, Osage and 

 Ste. Genevieve. 



'Proc. Bost. Soc. Nat. Hist, XXVI, p. 474; and A. J. S. (4), IV, p. 357. 



