Slide possibly prepared by Emmanuel Samuels (E.S).

Aulacodiscus oregonus is a species of diatom first identified and described by Professor William Henry Harvey and Professor Jacob Whitman Bailey in their publication “New species of Diatomaceæ, collected by the United States Exploring Expedition, under the command of Capt. Wilkes, U.S.N. Proceedings of the Academy of Natural Sciences of Philadelphia 6(11): 430-431.”