upper part, No Bentonites. Elk Butte is not Pierre-Fox Hills transition members. Transition Beds, (60- Sandy shale with dark shale partings. Contact with Elk Butte member of Pierre marked by "yellow zone." yellow zone has sulphur colored streaks in blue-gray clay shale. Fossilferous conchs come in above yellow zone. Gemellia conchs with little spheres other ammonites etc come in above. Color of transition-definitely buff on weathering. Fresh exposures also buff colored due to sand content.