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
Dehiscence (botany) Dehiscence (botany) Dehiscence is the splitting along a built-in line of weakness in a plant structure in order to release its contents, and is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part. Structures that open in this way are said to be dehiscent. Structures that do not open in this way are called indehiscent, and rely on other mechanisms such as decay or predation to release the contents. A similar process to dehiscence occurs in some flower buds (e.g., "Platycodon", "Fuchsia"), but this is rarely referred to as dehiscence unless circumscissile dehiscence is