http://hdl.handle.net/123456789/1382 2026-04-14T23:10:12Z http://hdl.handle.net/123456789/3759 The genetics of the butterfly Hypolimnasmisippus (L.): Smith, David, A.S; Gordon, I.J Hypolimnas misippus is a polymorphic and mimetic butterfly with a pantropical distribution. The polymorphism is autosomal and female-limited, the several female forms being generally regarded as Batesian mimics of the distasteful, toxic and polymorphic danaine butterfly Danaus chrysippus. The female phenotypes of H. misippus are described and classified. New data, from the rearing of 140 broods of H. misippus in Ghana and Sierra Leone, are analysed together with older material (21 broods) from other parts of Africa. Form misippus (genotype M-) is found to be genetically dominant to form inaria (genotype mm). However, a large proportion of mm butterflies has an intermediate phenotype, especially in association with white on the hindwing. Evidence is adduced to show that the genes giving hindwing white are variably epistatic over the ‘inaria’ pattern in the mm genotype, producing a phenotype transitional to or even identical to misippus. The various intermediate phenotypes are poor mimics of D. chrysippus: their abundance, geographical range and, hence, significance have been much underestimated. © The Genetical Society of Great Britain. 467-475p:, ill 1987-03-01T00:00:00Z http://hdl.handle.net/123456789/3758 Polymorphismof the tropical butterfly,danaus chrysippus l., in Africa Gordon, I.J. The polymorphism of Danaus chrysippus is anomalous since it is a distasteful butterfly. In a field study of the B locus polymorphism in Ghana, significant changes in the morph frequencies were recorded over eighteen months at Cape Coast. There were also significant differences between localities. There was some evidence that brown morphs are favoured by wet conditions, and that orange forms have higher survival rates as caterpillars. There were no differences between forms in larval foodplants, sex ratio, body size, wing damage, mating success, or in the effects of weather on adult activity. There was however, strong assortative mating between forms. Crosses with Kenyan females gave aberrant segregations for the sex chromosomes and the C locus. The results are discussed with regard to the hypothesis that polymorphism arose as a result of the overlapping of previously isolated geographical races. © 1984 The Genetical Society of Great Britain. 583-593p:, ill 1984-01-01T00:00:00Z http://hdl.handle.net/123456789/3757 Algae from the Rhynie Chert Edwards, David, S; Lyon, A. G New material collected from the Rhynie Chert Bed (Siegenian age) has revealed new filamentous and unicellular algae. Two of the filamentous forms and one palmelloid form are described. Filamentous and unicellular algae are particularly common in a white kind of chert not previously reported and which is interpreted as having been formed by the in situ silicification of a silicate‐rich pond. Some rhizoid‐nodes of Palaeonitella cranii (Kidston & Lang) Pia and a possible rhizoid‐borne pro‐embryo are also described and compared with similar structures in living Charophyta. Copyright © 1983, Wiley Blackwell. All rights reserved 35-55p:, ill 1982-07-01T00:00:00Z http://hdl.handle.net/123456789/3753 Diurnal periodicity in some common flowers YANNEY EWUSIE, J.; QUAYE, E. C. The time of flower opening and closure has been observed in twenty species belonging to nine different families. Increasing light initiates opening in some flowers and different species have different thresholds of response. Other species appear to be unaffected by light intensity. Experiments on the effect of photoperiod on petal movement in Talinum triangulare and Mirabilis jalapa indicate that the photo‐fraction affects the period of the rhythm by altering phase‐timing. A close correlation is suggested between phase‐timing and the automatic self‐pollination mechanism in Talinum possibly also in Mirabilis. Temperature also modifies the period of the rhythm in Tradescantia and Talinum; in the latter, a temperature of 24°C promoted closing. Copyright © 1977, Wiley Blackwell. All rights reserved 479-485p:, ill 1976-08-01T00:00:00Z