NO. 13 DIKELOCEPHALUS AND OTHER GENERA 361 



Upper Cambrian : (78b) St. Lawrence formation, 50 feet (15.2 m.) 

 above St. Croix River, near the landing- at Osceola, Polk County, 

 Wisconsin (Cooper Curtice, 1884). 



Lingulella mosia (Hall) Dikelocephalus ininnesotensis Owen ? 



Lingulella similis (Walcott) Saukia crassimarginata (Whitfield) 



Finkclnburgia osceola (Walcott) Osceolia osceola (Hall) 



Ozvenella cf. antiquata (Whitfield) Illcenurus quadratus Hall 

 Dikelocephalus ? limbatus Hall 



Saukia pepinensis (Owen) is found abundantly in the St. Law- 

 rence formation (113, p. 360). 



Saukia fallax (Locality 70a, p. 359) from Texas appears to be an 

 Upper Cambrian species restricted to one locality and horizon as 

 far as now known. 



Saukia leucosia and 6^. pyrene both occur in the upper portion of 

 the St. Lawrence formation at locality 78 in the following associa- 

 tion: 



Locality 78 : Upper Cambrian : St. Lawrence formation ; quarry 

 near St. Croix River, in suburbs of Osceola, Polk County, Wisconsin 

 (L. C. Wooster, 1883). 



Obolus (IVestonia) aurora (Hall) Spirodentalium osceola Walcott 



Lingulella mosia (Hall) Ouieiiella antiquata (Whitfield) 



Lingulella mosia osceola (Walcott) Holopea ? siveeti Whitfield 



Lingulella winona (Hall) Ophileta (Raphistoma) primordialis 

 Lingulella winona convexa (Walcott) A. Winchell 



Billingsella coloradoensis (Shumard) Dikelocephalus ? limhatus Hall 



Finkelnburgia finkelnburgi (Walcott) Saukia leucosia Walcott 



Finkelnburgia osceola (Walcott) Saukia pyrene Walcott 



Finkelnburgia osceola corrugata Osceolia osceola (Hall) 



(Walcott) Illcenurus quadratus Hall 

 Syntrophia barabuensis (A. Winchell) 



Saukia marica is at the upper line of the Cambrian in Nevada. At 

 locality 62 it is associated with the following : 



Upper Cambrian: (62) Limestone in the Dunderberg shale in 

 canyon immediately north of Adams Hill, Eureka district. Eureka 

 County, Nevada (C. D. Walcott, 1880). 



Micromitra sculptilis Meek Agnoslus prolongus Hall and Whit- 



Obolus discoideus (Hall and Whit- field 



field) Pagodia breviceps ? (Walcott) 



Lingulella manticula (White) Saukia marica (Walcott) 



Lingulella punctata (Walcott) Arcthnsina ? americana Walcott 



Acrotreta spinosa Walcott 



Agnostus communis Hall and Whit- 

 field 



