Pollen Analysis Circular maintain contact with one another and maintain publication lists that had, until then, been published by Gunnar Erdtman as "Literature on Pollen Statistics and Related Topics". The first issue of the "Pollen Analysis Circular" was dated May 5, 1943 and published by Paul B. Sears (Oberlin College). Subsequent issues were generally edited by Sears, sometimes in cooperation with L.R. Wilson. In January 1945, the "Pollen Analysis Circular" was renamed the "Pollen and Spore Circular" to more accurately reflect its scope. After 1954, the Circular was incorporated into the "Micropaleontologist", soon renamed "Micropaleontology", published by the American Museum of Natural History.
Gum (botany) Gum (botany) Gum is a sap or other resinous material associated with certain species of the plant kingdom. This material is often polysaccharide-based and is most frequently associated with woody plants, particularly under the bark or as a seed coating. The polysaccharide material is typically of high molecular weight and most often highly hydrophilic or hydrocolloidal. Many gums occur as seed coatings for plant species; the adaptive purpose of some of these gummy coatings is to delay germination of certain flora seeds. An example of such a gummy coating occurs in the case of Western poison oak, a widespread shrub