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Andrew C Rozefelds 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):459-462
A fossil described as Lepidostrobus muelleri Johnston is referred to temnospondyl amphibians and is shown to have affinities with either the Rhinesuchidae or the Rhytidosteidae. 相似文献
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Andrew Rozefelds Mary Dettmann Trevor Clifford Scott Hocknull Nikki Newman Henk Godthelp 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):24-39
Computed tomography (CT) and traditional techniques were used to study the internal morphology of modern fruits of Pleiogynium timoriense (DC.) Leenh., and phosphatized and silicified fruits that were considered to belong to the genus. The results demonstrate that phosphatized fruits from the Oligocene–Miocene Dunsinane site at Riversleigh and silicified fruits from the Oligocene Glencoe Site, which are both in Queensland, are referable to Pleiogynium. The Riversleigh material (Pleiogynium wannanii Rozefelds, Dettmann & Clifford sp. nov.) is very similar to extant P. timoriense (DC.) Leenh. Both possess locules that, in the vertical axial plane, are asymmetrically reniform and enclosed by a two-layered endocarp, the inner layer woody and resistant to decay, the outer of fibres and parenchyma, surrounded by a mesocarp of fibres and sclereids and a parenchymatous exocarp. The outer mesocarp is sculpted by meridionally arranged, elongate depressions (germination apertures) situated at the dorsal surface of each locule; erosion of the mesocarp and outer endocarp provides passage for emergence of the embryo’s radicle on germination. The silicified material from Glencoe (P. parvum Rozefelds, Dettmann & Clifford sp. nov.) is smaller in all its parts and has locules that are ovate in the vertical axial plane. Discrete, cap-like, opercula are not evident in the fruit wall of the fossil and extant fruits studied. The presence of Pleiogynium, and associated taxa, indicates the existence of rainforest communities at Glencoe, and mixed open forest/rainforest at Riversleigh during Oligocene–Miocene times. The multilocular, fossil fruit described as Pleiogynium mitchellii Collinson, Manchester and Wilde from the Eocene deposits at Messel Quarry, Germany, is not considered to belong in the genus, as evidence of elongate depressions on the dorsal surface of the fruit stones has not been demonstrated conclusively, and its internal morphology/anatomy differs significantly from that of Pleiogynium. 相似文献
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Andrew Gardner 《Oxford Journal of Archaeology》1999,18(4):403-418
Changes in the material culture of the late Roman army in Britain mean that it is often difficult to identify archaeologically. Some of these changes have in the past been taken as symptoms of decline, without attempt at further explanation. This paper aims to explore these changes and their deeper significance, within a theoretical framework which stresses the importance of the use of material culture in the expression of identities. Building from a detailed case study of fourth century occupation at Caerleon, it will be suggested that categorising material as ‘civilian’ or ‘military’ obscures complex patterns of both uniformity and variation between different kinds of site. These have implications not only for our understanding of the army in fourth and fifth century Britain, but also for society in general at this time, as it is within this wider context that the army should be seen. 相似文献
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