. Bulletin of the British Museum (Natural History). 56 WATSON AND BATTEN. Figs 64-66 Pilasporites allenii Batten, the probable dispersed spore of Equisedtes lyellii (Mantell). 64, 65. V,63073. x 1000. 64. spore showing subcircular patch of thickened exine and scattered granules on closely-adhering perine. 65. typical specimen of P. allenii with membranous perine closely enveloping and crumpled against the exine. 66, cross section of spore showing thick, homogeneous exine surrounded by a thin perine bearing scattered granular bodies; , x 4000. Kedves (1979) to have possible alg
. Bulletin of the British Museum (Natural History). 56 WATSON AND BATTEN. Figs 64-66 Pilasporites allenii Batten, the probable dispersed spore of Equisedtes lyellii (Mantell). 64, 65. V,63073. x 1000. 64. spore showing subcircular patch of thickened exine and scattered granules on closely-adhering perine. 65. typical specimen of P. allenii with membranous perine closely enveloping and crumpled against the exine. 66, cross section of spore showing thick, homogeneous exine surrounded by a thin perine bearing scattered granular bodies; , x 4000. Kedves (1979) to have possible algal origins and identified as Psophosphaera intrapunctata (Kedves) Kedves, displays the sort of crumpling and scattered granular bodies that characterize the perine of Pilasporites allenii (compare Batten 1973: pi. 42, figs 10, 11 with Kedves 1979: pi. 3, fig. 1). None of these palynomorphs is, however, unequivocally identical with the Wealden spores. PALAEOENVIRONMENTAL SIGNIFICANCE Where Equisetites lyellii is preserved in position of growth it is typically associated with thinly interbedded mudstones and siltstones. The latter commonly occur in lenticular units within the finer-grained deposits, forming the 'passage beds" of Allen (1959, 1976). These are subaqueous sedimentary accumulations and, although conveniently referred to as 'soil beds" for descriptive purposes, are generally not regarded as palaeosols sensu stricto. Allen, however, regards them as fossil aquatic soils at the 'wet end' of a continuous spectrum of soils, all supporting plants, from totally wet through reed- swamp and marsh to subaerial (1976 and personal communi- cation). Well stratified weathering profiles indicating sub- aerial soils have been confirmed in the Wealden of northern France (Meyer 1976), but only suspected in southern England (Lake & Thurrell 1974, Allen 1976, 1981, Stewart 1981) where high rates of deposition and frequent erosion appear to have hindered their development. R
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