WALCOTT. J 



WISCONSIN. 171 



A review of Dr. Rouiinger's work on the Mount Stephen fossils by Mr. 

 0. D.Walcott resulted in his determining that Embolimus spinosa, Rora.= 

 Zacanthoides spinosus, Walcott; Embolimus rotundata, How.=Bathyuris- 

 cus howelli, Walcott; Ogygia serrata= Olenoides nevadensis, Meek; and 

 that Conocephalites cordillerce, Hom.=Ptychoparia cordillerce, Rom. 

 (sp.), and' Ogygia ff Tdotzi, Rom., are new to the previously known 

 Cambrian fauna. The genus Zacanthoides is proposed to include Ole- 

 noides typicalis, 0. spinosus, 0. levis, and 0. flagrieaudus, described in 1886. 

 There were also identified from the material studied by Dr. Rominger 

 Agnostus interstrictus, Acrotreta gemma, Kutorgina prospectensis, and 

 Hyolithellus micans. 1 Subsequently from the collection studied by Dr. 

 Rominger there were described by Mr. Walcott, Lingulella macconelli 

 Crania f columbiana, Acrotreta gemma var. depressa, Orthisina alberta, 

 Platyceras romingeri, Karlia stephenensis, Bathyuriscus (Kootenia) 

 dawsoni, and the genus Ogygopsis was proposed to include the Ogygia 

 klotzi of Rominger. Linnarssonia sagittalis was also identified. 2 



In 1890 Mr. 0. D. Walcott 3 described three new species from the 

 Highland range section of Central Nevada, referring them to the Upper 

 Cambrian. These species are Hyolithes attenuates, H. curvatus, and H. 

 (?) corrugatus. 



INTERIOR CONTINENTAL PROVINCE. 



This province includes the Upper Mississippi area, the eastern border 

 or Adirondack subprovince, the western border or Rocky Mountain 

 subprovince, and the Llano County area of central Texas and the 

 Grand Canon of Arizona as a minor southwestern subprovince. 



UPPER MISSISSIPPI AREA. 



• 



For convenience of reference the review of the literatuie pertaining 

 to Wisconsin, Minnesota, and Iowa is assembled for each State. The 

 Ozark area of southeastern Missouri is considered separately, and the 

 Lake Superior sandstones and the controversy in relation to them is 

 noticed under a distinct heading, after the description of the recognized 

 Upper Cambrian rocks of Wisconsin, Iowa, and Minnesota, and their 

 extension into Canada. This division also includes the references to 

 the Cambrian rocks of Michigan. 



WISCONSIN. 



In 1843, in notes on the geology of the Western States, Dr. D. D. 

 Owen called attention to the presence of a sandstone on the Mississippi 

 River, at Prairie du Chien, visible beneath the Lower Magnesian liine- 



1 Cambrian fossils from Mount Stephens. Am. Jour. Sci., 3d ser., vol. 36, 1888, p. 165. 

 a Descriptions of new genera and species of fossils from the Middle Cambrian. TJ. S. National 

 Museum, Proc, vol. 11, 1889, pp. 441-446. 

 » Description of new forms of Upper Cambrian fossils. U. S. Nat. Mus. Proc, voL 13, 1890, pp. 267-279. 



