SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 69, NO. 4, PL. 3 



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Fig. i. — Exeter sandstone in northeastern New Mexico, the supposed equivalent 

 of the Wingate sandstone exposed in the south wall of the canyon of the Dry 

 Cimarron, overlain by the Morrison and Purgatoire formations and Dakota sand- 

 stone. The sharp line at the base of the light-colored ledge is the unconformity 

 separating the Triassic red beds from the Jurassic. Photograph by W. T. Lee. 





FlG. i. — 1 he NavajO-McElmo contact in northeastern Arizona, showing the Navajo 

 sandstone below and the McKlmo formation above, separated by 3 feet of sandy 

 calcareous shale. Photograph by If. E. (Gregory. 



