Polished section of a algal cobble, showing a large subangular limestone nucleus and three distinct stage of growth, natural size. Sweetwater County, Wyoming. 1923.

Polished section of a algal cobble, showing a large subangular limestone nucleus and three distinct stage of growth, natural size. Specimen is from transitional beds between the Tipton tongue of the Green River formation and the Cathedral Bluffs tongue of the Wasatch formation in NE 1/4 SE 1/4 sec. 15, T. 25 N., R. 102 W. Sweetwater County, Wyoming. 1923. Plate 46-A in U.S. Geological Survey. Professional paper 154. 1929.