A-B. _Phosphatic-shelled brachiopods, the oldest fossils found in
the park. Actual width of specimens is about ¼ inch._
C-D. _Trilobites. Width of C is ¼ inch, D is ½ inch. National Park
Service photos by W. E. Dilley and R. A. Mebane._
[Illustration: A.]
[Illustration: B.]
[Illustration: C.]
[Illustration: D.]