Keywords: FMIB 38355 Mayflies on the gauge house on the big dam at Keokuk, Iowa, at 5-30 am, July 14, 1916 They were about equally numerous all along.jpeg check categories 17 September 2015 3 Mayflies on the gauge house on the big dam at Keokuk Iowa at 5 30 a m July 14 1916 They were about equally numerous all along the dam which is nearly a mile in length Subject Mayflies Keokuk Dam Iowa and Illinois Geographic Subject United States--Iowa--Keokuk United States--Illinois--Keokuk Tag Insects 1921 Cite book Burrowing Mayflies of Our Larger Lakes and Streams Bulletin of the United States Bureau of Fisheries vol 36 1917-1918 Needham James G Washington DC Government Printing Office 1921 Plate LXX-1 Emerson Stringham PD-UWASH-FMIB Institution University of Washington FMIB-source accession number 38355 Images from the Freshwater and Marine Image Bank to check Ephemeroptera Keokuk Iowa Keokuk County Iowa |