[[preprinted]] 0017 [[/preprinted]] 
Sept. 29, 30 
Ike's Canyon 
Sequence in brachiopod beds at top of canyon. 
[image: Sketch of Biostratigraphic diagram of area during the Silurian 
era.] 
Silurian| 
|Leptellina 
Sowerbyella 
| Rhysostrophia (coarse ribs) 
Toquimia, Valcourea 
Porambonites| Orthis (wide spaces between ribs fine-ribbed Rhyso 
Snails Aporthophyla| 
Sponges| 
Thin-bedded platy | 
G. Arthur Cooper - Field Notes and Maps, 1939 
Transcribed and Reviewed by Digital Volunteers 
Extracted Oct-09-2015 11:35:33 
Smithsonian Institution Transcription Center, Smithsonian Institution Archives 
