Summary
Several kinds of outgrowth from the grass ovule are known. Attention is focused here on one outgrowth that occurs within or around the micropyle and is of nucellar origin. Grass species in which it is currently known to occur are listed and examples of variants briefly described. Attention is concentrated upon Pennisetum, where the cell structure is described in detail with a series of electron photomicrographs. The tissue representing an aggregation of these transfer cells is newly named with the term ‘embellum’, and its significance for pollen tube growth is considered.
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Busri, N., Chapman, G.P. & Greenham, J. The embellum: a newly defined structure in the grass ovule. Sexual Plant Reprod 6, 191–198 (1993). https://doi.org/10.1007/BF00228648
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DOI: https://doi.org/10.1007/BF00228648