NO. 3 CAMBRIAN AND OZARKIAN TRILOBITES 1 37 



Anoria tontocnsis (Walcott) — Continued 

 Fig. 23. (Natural size.) Portion of a thoracic segment. U. S. Nat Mus 

 Cat. No. 62692. . ' 



24,25. (Natural size.) Ventral and side views of the associated 



hypostoma. U. S. Nat. Mus., Cat. No. 62689. 

 26,27. (Natural size.) Dorsal and side views of a typical pyoid- 



ium. U. S. Nat. Mus., Cat. No. 62694. 

 28. (Natural size.) A larger, but somewhat broken tail. U. S. Nat 

 Mus., Cat. No. 62693. 



Matrix, sandstone and olive micaceous shale. 



Upper Cambrian, Bright Angel shale. (Locs. 74 and 74e) : Grand 

 Canyon, Arizona. Specimens represented by figs. 15 and 16 com- 

 pressed in shale, others in sandstone, with natural convexity pre- 

 served. 



