ABSTRACT.

Nine species of Solaiuin namely, S. aethiopicum, S. ainericanum, S. eiiantliu,n, S. indicuin, S. nigrum, S. retrofleruin, S. scabruin, S trovuin and S. villosuin were investigated in this report with the aim of identifying the existing differences and similarities among them. The studies were carried out on the root, stem, leaf petiole, pollen and flower of the different species. The results obtained from this investigation showed features of anatomical, morphological, palynological and histochemical importance in the root, stern, leaf and petiole of the species. Results from cpderma1 morphology showed differences in shapes of the cells, wli':h varied fron rectangular, hexagonal to irregular or sinuous. Trichomes were found only in S. aethiopicuin, S. indicuin, S. scabruin and S. torvurn. These trichornes were present on the stern, leaf and petiole of these species. The types of trichoines varied: branched, multicellular trichomes, T-shaped stellate multicellular trichomes, long macro-uni senate hairs and gi an dul ar micro- hairs. Calcium oxalate crystals were found in different parts of all the species investigated: stem, leaf and petiole. Their shapes varied from pentagonal, hexagonal to irregular in S. aethiopicuin, S. arner..canum and S. villosuin and pen lagonal, hexagonal to spherical in other species. The shape and size of the pollen grains also differed among the species investigated, it ranged from spherical in S. aethiopicuin. S. american u/n, S. erianihumn, S. indicumn, S. retroflexunm, S. scabrumn, S. torvumn to angular in S. nigrumn and S. villosumn. The utilization of these features in the biological recognition and identification of these taxa were discussed.