BULL. GEOL. SOC. AM. 



VOL. 17, 1905, PL. 76 





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Figure 1. — Weathered Bighorn Limestone showing characteristic Network of Silica 

 The area in view is about 4 by 5 feet. Photograph by C. D. Waleott 



Figure 2. — Bighorn Limestone in Canyon of Owl Creek, near Longitude 109° 



View is taken looking down the canyon. The limestone constitutes the high cliff on the right. 

 The smaller cliffs are Madison limestone 



EXPOSURES OF BIGHORN LIMESTONE 



