| Cross-sections of silicified gastropods, Palliseria robusta (whitish specimens), in a block of dolomite from the upper part of the Middle Ordovician Pogonip Group, Dolomite Canyon, Death Valley National Park. Figure 3. |
Fossil Image From United States Geological Survey Bulletin 1299 Geology of the Panamint Butte Quadrangle, Inyo County, California, by Wayne H. Hall, 1971
| Cross-sections of silicified gastropods, Palliseria robusta (whitish specimens), in a block of dolomite from the upper part of the Middle Ordovician Pogonip Group, Dolomite Canyon, Death Valley National Park. Figure 3. |