The occurrence of silicified wood in the sands and gravels of the Tertiary of the Lower Mississippi Valley has long been known. Aside, however, from the numerous localities mentioned by Hilgard, nearly all of which are in the State of Mississippi, little attention has been given it. Numerous geologists have spoken of it or incidentally studied it in connection with other investigations, but hitherto no attempt has been made to recognize the species and fix their taxonomic value, if, indeed, they possess any such value. Among those who have investigated the Orange Sands and other Tertiary deposits of the Mississippi Valley and who have added to our information as to the occurrence of these fossils are Hilgard, Penrose, and Knowlton.
Proceedings of the Iowa Academy of Sciences
©1890 Iowa Academy of Science, Inc.
Call, R. Ellsworth
"The Tertiary Silicified Woods of Eastern Arkansas,"
Proceedings of the Iowa Academy of Science, 1(Pt. 2), 37-43.
Available at: https://scholarworks.uni.edu/pias/vol1/iss2/23