NO. 3 CAMBRIAN AND OZARKIAN TRILOBITES I4I 



PAGE 



Symphysurina eugenia Walcott 113 



Figs. 25-28. (Natural size.) More or less broken cranidia preserving 

 general shape. U. S. Nat. Mus., Cat. No. 70330. 

 29. (Natural size.) A small free cheek. U. S. Nat. Mus., Cat. 



No. 70331. 

 31. (Natural size.) Small associated pygidia. U. S. Nat. Mus., 



Cat. No. 702,2,2. 

 2,2. (Natural size.) An associated broken free cheek and pygid- 

 ium. U. S. Nat. Mus., Cat. No. 70222i- 



Matrix, limestone. 



Ozarkian, Mons formation. (Loc. 65v) : Clearwater Canyon, 

 Alberta, Canada. 



