BULL. GEOL. SOC. AM. 



VOL. 27, 1915, PL. 19 



Figure 1. — Devonian-Silurian Disconformity, Buffalo., New York 



Middle Devonian (Onondaga) limestone rests on the Silurian (Manlius) ; below is shown 

 another break (Manlius-Bertie) 



Figure 2. — Projecting Ledges of Eocene (Midway) Limestone disconformable on 

 Cretaceous Shale (Escondido), White Bluff, Rio Grande, Texas 



Photograph by L. W. Stephenson, U. S. Geological Survey 



ILLUSTRATIONS OF DISCONFORMITIES 



