Pollen Analysis Circular The last issue of the "Pollen and Spore Circular" (#18) was edited by Calvin J. Heusser and announced the fusion, indicating that "the spore and pollen section will constitute four to six pages in each issue and contain essentially the same material" as in the "Pollen and Spore Circular". The final issue also included abstracts from the First Palynology Conference (February 25, 1953), held at Yale University as well as correspondence from researchers working as far afield as Düsseldorf, Lucknow, and Indianapolis. It was in the pages of the "Pollen Analysis Circular" that the field of pollen analysis was given
Tylosis (botany) Tylosis (botany) A tylosis (plural: tyloses) is a bladder-like distension of a parenchyma cell into the lumen of adjacent vessels in wood. Less certainly, the term tylosis is in use to summarise the physiological process and the resulting occlusion in the xylem of woody plants as response to injury or as protection from decay in heartwood. It is a key process in wall one of the Compartmentalization Of Decay In Trees (CODIT) and other woody plants. Observed in section under a microscope, tyloses appear as balloon-like protrusions emanating from axial paratracheal parenchyma cells into xylem vessels through pits linking the