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61.
New isolated pterodactyloid bones from the Toolebuc Formation are described. The first one consists of a complete wing metacarpal 212 mm long, representing an individual with an estimated wing span of 4 m. Small depressions on the anterior surface are present and represent tooth marks showing that this specimen was subjected to scavenging prior to fossilization. The other bone consists of a three-dimensionally preserved cervical vertebra lacking most of the neural arch. The specimens are clearly referable to the derived pterosaur clade Pterodactyloidea. Based on several features such as the position of the pneumatic foramen and the particular shape and proportions of those elements, they possibly are members of, or closely related to, the Anhangueridae. The record of the Australian pterosaurs is reviewed here and represents the known southern distributional limit for Cretaceous pterosaurs, arguing against some older ideas of a more geographically restricted range for these flying reptiles.  相似文献   
62.
Books received     
The Lake‐Dwellings of Europe : being the Rhind Lectures in Arch?ology for 1888. By Robert Munro, M.A., M.D. Cassell and Co., 1890. Pp. xl. and 600.

Journeys in Persia and Kurdistan, including a Summer in the Upper Karun Region and a Visit to the Nestorian Rayahs. By Mrs. Bishop (Isabella L. Bird). Two volumes. London : John Murray, 1891. Price 24s.

My Mission to Abyssinia. By Gerald H. Portal, C.B., H.B.M. Agent and Consul‐General at Zanzibar. With Map and Illustrations. London : Edward Arnold, 1892. Pp. 261.

A Transatlantic Holiday; or, Notes of a Visit to the Eastern States of America. By T. Fitzpatrick, M.A. London : Sampson Low, Marston, and Co., 1891. Pp. viii + 210. Price 10s. 6d.

A Winter Cruise in Summer Seas. By Charles C. Atchison. London : Sampson Low and Co., 1891. Pp. 369. Price 16s.

Aus dem Kaukasus. Von C. Hahn. Leipzig : Verlag von Duncker und Humblot, 1892. Pp. 299. Price M. 6.

The New Era in Russia. By Charles A. de Arnaud. London : Gay and Bird. N.D. Pp. 166. Price 2s. 6d.

The Australian at Home. By Edward Kinglake. London : The Leadenhall Press. Pp. 159.

Illahun, Kahun, and Gurob, 1889–90. By W. M. Flinders‐Petrie, with Chapters by Professor Sayce, D.D., Professor Mahafft, Canon Hicks, F. Ll. Griffith, B.A., and F. C. J. Spurrell, F.G.S. London : David Nutt, 1891. Pp. 59, and Plates xxxiii.

Africa Rediviva, or the Occupation of Africa by Christian Missionaries of Europe and America. By Robert Needham Cust, LL.D. London : Elliot Stock, Pp. 118.

The Negro Question; or, Hints for the Physical Improvement of the Negro Race, with special reference to West Africa. By Joseph Benner Maxwell, M.A., B.C.L. (of Merton College, Oxford). London : T. Fisher Unwin, 1892. Pp.188.

Oliver &; Boyd's Edinburgh Almanac and National Repository for the year 1892. Edinburgh : Oliver &; Boyd. Pp. 1195. Price 6s. 6d.

An Almanack for the year of Our Lord 1892. By Joseph Whitaker, F.S.A. London. Pp. 728.

Hazell's Annual for 1892 : A Cyclop?dic Record of Men and Topics of the Day. London : Hazell, Watson, and Viney, Ld., 1892. Pp. 726. Price 3s. 6d.

Barker's Facts and Figures for the Year 1892. Edited by Thomas P. Whittaker. London and New York : Frederick Warne and Co. Pp. 384. Price 1s.

North Wales. Part II. By M. J. Baddeley, B.A. and C. S. Ward, M.A. Third Edition, revised. “Thorough Guide Series.” London : Dulau and Co., 1891. Pp. xvi+147. Price 2s. 6d.

Lochnagar. By Alex. Inkson M'Connochie. Aberdeen: D. Wyllie &; Son. 1891. Price 1s.

Handbook to the Geology of Derbyshire. By Rev. J. Mageno Mello, M.A., F.G.S. 2d Edition. London : Bemrose and Sons, 1891. Pp. 89.  相似文献   
63.
This paper presents the motivation, procedures, and results of an experiment that examines short episodes of animal trampling in dry and water saturated substrates in South India. While horizontal artifact displacement was similar to that modeled by other trampling experiments, vertical artifact displacement in water saturated substrates was greater than any reported experiment to date. The toolstone used in this experiment, a silicious limestone, exhibited minimal damage after trampling. Artifact inclination patterning appeared to be a potentially diagnostic middle-range marker of trampling in water saturated substrates. Given the abundant number of Paleolithic sites that are located on flat, open surfaces near water-bodies, or experience monsoonal climatic regimes, we propose that future excavations should measure artifact inclination on a regular basis.  相似文献   
64.
We present a structural, microstructural, and stable isotope study of a calcite vein mesh within the Cretaceous Natih Formation in the Oman Mountains to explore changes in fluid pathways during vein formation. Stage 1 veins form a mesh of steeply dipping crack‐seal extension veins confined to a 3.5‐m‐thick stratigraphic interval. Different strike orientations of Stage 1 veins show mutually crosscutting relationships. Stage 2 veins occur in the dilatant parts of a younger normal fault interpreted to penetrate the stratigraphy below. The δ18O composition of the host rock ranges from 21.8‰ to 23.7‰. The δ13C composition ranges from 1.5‰ to 2.3‰. This range is consistent with regionally developed diagenetic alteration at top of the Natih Formation. The δ18O composition of vein calcite varies from 22.5‰ to 26.2‰, whereas δ13C composition ranges from ?0.8‰ to 2.1‰. A first trend observed in Stage 1 veins involves a decrease of δ13C to compositions nearly 1.3‰ lower than the host rock, whereas δ18O remains constant. A second trend observed in Stage 2 calcite has δ18O values up to 3.3‰ higher than the host rock, whereas the δ13C composition is similar. Stable isotope data and microstructures indicate an episodic flow regime for both stages. During Stage 1, formation of a stratabound vein mesh involved bedding‐parallel flow, under near‐lithostatic fluid pressures. The 18O fluid composition was host rock‐buffered, whereas 13C composition was relatively depleted. This may reflect reaction of low 13C CO2 derived by fluid interaction with organic matter in the limestones. Stage 2 vein formation is associated with fault‐controlled fluid flow accessing fluids in equilibrium with limestones about 50 m beneath. We highlight how evolution of effective stress states and the growth of faults influence the hydraulic connectivity in fracture networks and we demonstrate the value of stable isotopes in tracking changes in fluid pathways.  相似文献   
65.
Unusual cone‐shaped iron oxide concretions occur in the Late Triassic, lower fluvial sandstone member of the Trujillo Formation at Palo Duro Canyon in the Texas panhandle. In situ concretions are significant because they record both historical information about past processes that occurred within the geologic unit and present‐day information about the ability of the unit to conduct fluids. The dominant orientation of the concretions is cone‐apex up, body radiating down and out, with long axis perpendicular to bedding. Concretion morphologies are associated with the sedimentary texture and primary bedding structure of the host rock and the corresponding hydrologic regime (i.e. advection versus dispersion for iron‐transport behavior). Three lithofacies in the lower Trujillo member exhibit different cone forms. Field observations of cone orientation and morphology suggest vadose conditions for diagenetic precipitation of iron oxide cements, with timing potentially represented by the major pre‐Miocene unconformity.  相似文献   
66.
Soqotra Island, the remote border outpost of the Yemeni state in the Indian Ocean, is a community of mixed ethnic composition with a non‐Arabic mother tongue. It offers an ideal socio‐political context for the study of state–community relations in terms of polity formation as part of a political incorporation process. This focus provides a corrective to the still dominant segmentary society paradigm and its tribes‐driven state politics in the anthropological discourse on Yemen. Polity formation in Soqotra occurred through a series of acts of political incorporation by a succession of political regimes from the late nineteenth century to the present. The study of this process is pursued through a historical narrative of the state’s politics of administration. This narrative is aptly described as a mesography, as its analytical focus is on the meso‐level institutional web of four different political regimes with their distinctive modes of polity regimentation and their structuring effects on Soqotrans’ communal life.  相似文献   
67.
Lithic analysis, radiocarbon dating and luminescence dating are applied to a stratified open-air Paleoindian site in Central Brazil, lending some balance to a published record dominated by rock shelter sites. Most lithics are found in two discrete occupation layers. Lithics found outside these layers are attributed to post-depositional movement of small flakes mainly upwards. Single-grain luminescence dating on quartz grains also suggest post-depositional movement. Both wind and bioturbation are suspected mechanisms. The luminescence analysis does not provide precise depositional dates in this situation but does support such dates suggested by radiocarbon.  相似文献   
68.
Formation processes and chronology are central to many archaeological endeavours, and accuracy in the latter is dependent on control of the former. Here we consider how to integrate geoarchaeological and chronometric evidence to better understand the formational history, along with the timing and duration of cultural activities, at a regionally significant site in the southern Cook Islands (Polynesia) which dates from ∼12th century AD. Initially we model natural and cultural processes of deposition using geoarchaeological evidence. The results are integrated with 21 radiocarbon dates, including nine new AMS results on identified medium and short-lived materials. Sample outliers are identified manually and statistically and a Bayesian analysis helps to refine age estimates for the site's 12 stratigraphic zones. The timing and rate of sediment accumulation is further considered through an age–depth model. Finally, the chronology developed from these combined approaches is used to address three key processes: 1) initial site use, potentially relevant to human colonisation of this Polynesian island and archipelago; 2) on-site activities and patterns of resource use; and 3) major marine deposition events which disrupted cultural activities and may have palaeoclimatological significance. The approach developed here potentially has utility elsewhere, particularly where human activities are recurrent and of limited duration.  相似文献   
69.
Bittencourt, J.S., Leal, L.A., Langer, M.C. & Azevedo, S.A.K., June 2012. An additional basal sauropodomorph specimen from theUpperTriassic Caturrita Formation, southern Brazil, with comments on the biogeography of plateosaurids. Alcheringa, 1–10. ISSN0311-5518.

We describe an additional saurischian specimen from the Caturrita Formation (Norian) of the Parana Basin, southern Brazil. This material was collected in the 1950s and remained unstudied due to its fragmentary condition. Detailed comparisons with other saurischians worldwide reveal that some characters of the ilium, including the low ventral projection of the medial wall of the acetabulum and its concave ventral margin, together with the short triangular shape of the pre-acetabular process and its mound-like dorsocaudal edge, resemble those of sauropodomorphs such as Plateosaurus and Riojasaurus. This set of traits suggests that MN 1326-V has affinities with basal Sauropodomorpha, probably closer to plateosaurians than to Saturnalia-like taxa. Previous records of this clade in the Caturrita Formation include Unaysaurus, which has been related to Plateosaurus within Plateosauridae. Alternative schemes suggest that plateosaurids include Plateosaurus plus the Argentinean ‘prosauropods’ Coloradisaurus and Riojasaurus. Both hypotheses raise biogeographic questions, as a close relationship between faunas from South America and Europe excluding Africa and North America is not supported by geological and biostratigraphical evidence. Additionally, the absence of plateosaurids in other continents suggests that the geographical distribution of thistaxon is inconsistent with the geological history of western Pangaea, and this demands further investigations of the phylogeny of sauropodomorphs or improved sampling.

J.S. Bittencourt* [sigmaorionis@yahoo.com.br] Laboratório de Paleontologia, Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 1404901, Ribeirão Preto, SP, Brazil. Fellow FAPESP; L.A. Leal, Departamento de Ciências Biológicas, Universidade Estadual do Sudoeste da Bahia, Rua José Moreira Sobrinho, s/n, 45206-190, Jequié, BA, Brazil; M.C. Langer, Laboratório de Paleontologia, Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 1404901, Ribeirão Preto, SP, Brazil; S.A.K. Azevedo, Laboratório de Processamento de Imagem Digital, Departamento de Geologia e Paleontologia, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista s/n, 20940-040, Rio de Janeiro, RJ, Brazil. Received 29.7.2011; revised 10.10.2011; accepted 18.10.2011.  相似文献   
70.
Seven selachian scale types are described from the middle Cenomanian Moonkinu Formation, outcropping on the southern shores of Bathurst Island in northern Australia. The scales are classified in accordance with previously published scale morphologies of Cretaceous and modern sharks, and are representative of the Orders Squatiniformes (Family Squatinidae), Carcharhiniformes (Family Scyliorhinidae), and Lamniformes (Family Odontaspididae). The presence of typically bottom-dwelling, shallow-water angelsharks (squatinids), catsharks (scyliorhinids), and sand tiger sharks (odontaspidids) within the Moonkinu Formation support an inner neritic depositional environment interpretation for the unit, previously determined from foraminiferal biofacies and lithology. The biostratigraphic potential of these scales can only be assessed after scales from more Cretaceous localities are described and documented.  相似文献   
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