OF WESTERN NORTH AMERICA. 



39 



as known. H. G. Stehlin^ supports the wTiter's opinion that Kiiti- 

 meyer was too prone to identify European with American genera; 



KNIGHT "~1 -T T Types of Eohippus index 



" " yassac,ens,s 

 " " Phenacodus prlmae^us 

 " " Coryphodon radians 

 " " " ■ semicinctus 

 faticeps 



Volcanic ash or 

 white beds 



Plants characteristic 

 of Deni^er formation 



Plants and 

 invertebrates 

 of Montana 

 age 



-Fig. 4.— Columnar section showing the relations of the typical Wasatch section, including the Knight 

 formation (near Knight, Wyo.), or Coryphodon zone, to the overlying and underlying formations. 

 After Veatch, 1907. 



this removes the American resemblances supposed to exist in the 

 Egerkingen fauna, which now proves to be of middle Eocene (Lute- 



a In letter dated July, 1906, Doctor Stehlin states that he is himself engaged in the study of migra- 

 tions. He, too, finds stro;ig evidence (1) for a lower Eocene connection tetween America and 

 Europe, (2) for a very decided separation during the middle and upper Eocene, and (3) for a renewed 

 connection in the Oligocene and a great Oligocene faunal interchange. These are substantially the 

 views adopted in the present paper. 



