Vlll BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



Shimer and Grabau: Page 



Figure 1 — Section A — One side of railroad cut near Thedford 151 



2— Section B— North of Thedford 152 



3-Section C— Brickyard 153 



" 4 — Section D — Wall of Rock glen, near Arkona 155 



" 5 — Section E — Bank of Riviere aux Sables at Bartlett's mill 



(Marshall's mill) : la = Platyceras arkonense bed 157 



Clark and Bibbins: 



Figure 1 — Generalized vertical section across Atlantic coastal plain. ... 212 



Brooks : 



Figure 1 — Geological map of southeastern Alaska 257 



Coleman : 



Figure 1 — Geological map of Helen mine 294 



" 2 — Sections near Helen mine 296 



Willis : 



Figure 1 — Map of northwest Montana 309 



1 ' 2 — Sketch of northern end of Lewis range 329 



" 3— Mounts Heavens and Stanton, looking south from Trapper 



peak 330 



" 4 — Diagram of strikes and dips of planes subtending areas of 



the Lewis thrust ... 332 



" 5 — Chief mountain, looking north 334 



" 6 — Structure of Yellow mountain, drawn from photograph from 



Chief mountain, looking southeast x 335 



Watson : 



Figure 1 — Virglina copper district, Virginia and North Carolina 358 



(58 plates; 47 figures.) 



