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.
Cortex (botany) cylinder of the root through diffusion and may also be used for food storage in the form of starch. Cortex (botany) A cortex is the outermost layer of a stem or root in a plant. In botany, the cortex is the outermost layer of the stem or root of a plant, bounded on the outside by the epidermis and on the inside by the endodermis. In plants, it is composed mostly of differentiated cells, usually large thin-walled parenchyma cells of the ground tissue system. The outer cortical cells often acquire irregularly thickened cell walls, and are called collenchyma cells. Some