Epidermal morphology of six taxa of Ipomoen L. in Nigeria With one Figure, 2 Tables and 2 Plates S u m m a r yStomatal measurements, SL/xB, distribution, types and structural variations are discussed for six taxa of rpomoea L. in Nigeria. Considerable overlaps are recorded in the stomatal quantitative measurements. The taxa investigated are amphistomatous but with higher frequency of stomata on the abaxial surface. The paracytic stomata are frequent and common to all the taxa studied. Nevertheless, the anisocytic, cdntiguous, amphianisocytic and hemiparacytic types are recorded for the first time in these Nigerian taxa of the genus.Explanations to Plates I and I1

The species are made up of three ploidy levels of chromosome complements with haploid number of n = 16 for the two varieties of Amaranthus hybridus, n = 17 for the two varieties of A. spinosus and A. viridis and n = 32 for A. dubius. All the species are characterised by aberrant meiosis except A. dubius. High degree of meiotic abnormalities such as multivalents and stickiness of chromosomes leads to clumping, overlapping of chromosomes and unequal segregation of chromosomes at anaphyse I. The measurements of the pollen grains showed some overlaps with the size distribution ranging from 23.52–35.28 μm. The species are highly fertile with over 85% pollen stainability except A. dubius and A. hybridus, green variety that had between 65.8% and 72% respectively. The stomata are of pericytic and anomocytic types and they showed a high degree of overlaps in their xL/xB. The high degree of overlaps in most of the micromorphological features confirms the closeness of the species and the difficulty in separating the species.

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