Pe ATH, Xe eV 
EOPHYTON (?) (p. 63). 
Fias. 1, 2. Views of casts of trails on the under side of a thin slab of the Middle Cambrian (Tonto) 
sandstone. (Collection United States National Museum. ) 
Fic. 3. View of casts of trails on the St. Croix sandstone of Wisconsin. (Collection United 
States National Museum.) 
