248 C. W. TOMLINSON 



in the Red Lion formation (250 feet thick) of the Philipsburg 

 quadrangle, Montana, from which Kindle 1 has made some collec- 

 tions identified by Walcott 2 as Upper Cambrian. 



The beds in question probably are equivalent to some part or 

 parts of Member 3 of the Utah sequence, and it is therefore possible 

 that they may include strata of Lower Ordovician age. 



The Maxfield formation of the central Wasatch. — Hintze 3 has 

 described a sequence of 481 feet of limestones and shales "discon- 

 formably overlying the Alta shale" 4 on the South Fork of Big 

 Cottonwood Canyon, southeast of Salt Lake City, which he has 

 named the Maxfield formation, and has tentatively assigned to 

 the Ordovician. The Alta shale (150-200 feet thick), which rests 

 on the basal Cambrian quartzite, carries a Lower Cambrian fauna 

 near its base and a Middle Cambrian fauna at a higher horizon. 5 

 Disconformably above the Maxfield lies the Devonian Benson 

 limestone. 



No fossils have been found in the Maxfield formation. Its 

 reference to the Ordovician was suggested by the "wormy " appear- 

 ance of the chief limestone members of the formation, which Hintze 

 likened to the Lowville ("Birdseye") limestone of New York, and 

 by the occurrence at the top of the formation of 10 feet of shale 

 alternating with typical flat-pebble ("edgewise") limestone con- 

 glomerate, which Hintze 6 noted had been described from Lower 

 Ordovician strata elsewhere. Unfortunately for this correlation, 

 conglomerate of that type is abundantly developed in northern 

 Utah, not only in the Garden City (Beekmantown) formation, but 

 in the St. Charles (Upper Cambrian) and Bloomington (Middle 

 Cambrian) formations. The "wormy" appearance is to be seen 

 in various members of each and all of the six Middle and Upper 



1 E. M. Kindle, "Fauna and Stratigraphy of the Jefferson Limestone in the 

 Northern Rocky Mountain Region," Bull. Amer. Pal., No. 20, 1908, pp. 10-n; also 

 Emmons and Calkins, op. tit., p. 63. 



2 C. D. Walcott, op. cit. ult., p. 233, Lots 3025, 302?-. 



* F. F. Hintze, Jr., "A Contribution to the Geology of the Wasatch Mountains, 

 Utah," Annals New York Acad. Sci., XXIII (1913), 85-143. 



* Ibid., p. 105. 



s C. D. Walcott, U.S. Geol. Survey, Bull. No. 81, 1891, p. 319. 

 6 Op. cit., p. 106. 



