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Seeds of Williamsonia collected from Amarjola in the RajmahalHills, Bihar, are described. Mature seeds are found in ripe,naked, bractless fructifications. Seeds are oblong or ovate,stalked, dicotyledonous, partially endospermic, and have longmicropyles. The seed coat is differentiated into an outer coveringof tubular cells, middle parenchymatous true integument, andan inner vascularized layer which forms after fertilizationand as a result of modification of the peripheral portion ofnucellus. 相似文献
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Three types of petrified filician rhizomes and their associatedpetioles and roots from the Rajmahal Hills, Bihar, India aredescribed. Two rhizomes possess protostelic vasculature withmesarch protoxylem elements and exarch protoxylem points. Theformer are gleicheniaceous while the latter is described asa schizaeaceous rhizome. The associated petioles possess typicalgleicheniaceous anatomy while the roots show variations in thestructure of epiblema and cortex. filician fossils, Jurassic, Actinostelopteris pakurense, Gleichenia sonajoriense, Solenostelopteris jurassica, Gleichenioamyelon diarcha, Filicoamyelon cryptogrammoides Filicoamyelon actinostachyoides 相似文献
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Kaushalaya Nandan Gaur 《Revue de Micropaléontologie》2009,52(3):227
A prolific foraminiferal assemblage comprising 51 species is reported from Jurassic sediments of the Chari Formation, Jumara Hills, Kutch, India. The assemblage is dominated by the families Vaginulinidae and Nodosariidae. Sixteen species are reported for the first time from the Indian region including one new species. The foraminiferal assemblage suggests a Callovian to Oxfordian age for the studied sequence. The depositional environment of the studied sequence is interpreted based on foraminiferal evidence combined with lithology and megafauna which indicates that the sediments of the Chari formation exposed at Jumara Hills were deposited in a shallow-water, near shore, environment with fluctuating shoreline in a tectonically unstable shelf zone. The Jumara Hills foraminiferal assemblage exhibits close affinity with certain other Jurassic assemblages of the Tethyan Realm and helped in drawing palaeogeographic conclusions, suggesting that during the Middle and Late Jurassic epochs Kutch had close sea connections with Central Arabia, Afghanistan and Rajasthan on the one hand and Somalia and Malagasy on the other. 相似文献
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Diversity of vascular plants was studied in three sacred groves of the Jaintia Hills, in northeast India. About 395 species, 250 genera, and 108 families comprising pteridophytes, gymnosperms and angiosperms were found in the groves. Orchidaceae, Rubiaceae, Asteraceae and Lauraceae were dominant families and Ficus was the largest genus, with nine species. About 160 tree species were distributed in canopy, subcanopy and under canopy strata of the forest. Concentration of tropical and temperate elements of the neighbouring Sino-Himalayan and Burma-Malayan regions, and endemic (54 species), rare (31 species) and primitive taxa (38 species) due to favourable climatic conditions and prolonged protection have contributed to the high species richness of the groves. Their better management and protection is important for the conservation of plant diversity in the region and also for the benefit of indigenous tribes of the state. 相似文献
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Sreepat Jain John H. Callomon Dhirendra K. Pandey 《Pal?ontologische Zeitschrift》1996,70(1-2):129-143
Two specimens of the Middle Jurassic ammonite genusReineckeia (sensu lato) have been found in the lowest beds of the Pachchham (Patcham) Limestones exposed in the core of the Jumara Dome, Kachchh (Kutch), Gujarat, western India. The stratigraphy is described in detail and the age bracketed to lie between latest Late Bathonian and Middle Bathonian, older than any previously described examples of this genus, either in India or in Europe (middle Early Callovian). The new finds are compared with other known pre-Callovian Reineckeiidae, notably those of the eastern borders of the Pacific, but the relationships are not close. The phylogenetic consequences are briefly discussed. The roots of the Reineckeiidae continue to lie hidden. 相似文献
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Choudhary RP 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2001,59(1):61-71
The nutritional status of preschool children of the three sects of the Pahariya tribe (Rajmahal Hills, Bihar) was studied with the help of anthropometric indices like weight for age, height for age, weight for height und nutritional deficiency signs. The correlation between age and nutritional indices showed that the relationship was significant for % expected weight for age in the male children of all the three sects; r = +0.70 in Saurias, r = +0.32 in Mals and r = -0.72 in Kumarbhags (p > 0.01). Significant relationships were also observed in the correlations between weight for height in both sexes. Based on height for age and weight/height2 (Body Mass Index, BMI), 89% of the children of the Saurias, 92% of the Mals and 93% of the Kumarbhags were malnourished. Height for age of 50% of the children of the Pahariyas were below the 3rd percentile or below 90% of the Harvard standard. Chronic and current severe forms of malnutrition (i.e. height for age below 3rd percentile of standard and BMI 13.5) was highest in the Kumarbhags (17.5%). According to the modified Waterlow's classification chronic and current severe forms of malnutrition (i.e. height for age below 3rd percentile of the National Centre for Health Statistics, NCHS, and weight for height less than 80% of the standard) was highest in the Saurias (21.6%) and least in the Kumarbhags (15.4%). Kwashiorkor and marasmus for all the children of the Pahariyas ranged between 0.5-1.4% and 1.5-5.2%, respectively. Associated with signs of Protein Caloric Malnutrition (PCM), like moon face, dyspigmentation, sparseness and easy pluckability were more prevalent in all the three sects of the Pahariyas. Ocular manifestation of vitamin-A deficiency like conjunctiva xerosis and Bitos' spots were also frequent among these children. 相似文献
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Middle Jurassic calcareous algae from the circum-Arabian area 总被引:1,自引:0,他引:1
Dr. Jochen Kuss 《Facies》1990,22(1):59-85
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Economic Botany - This paper deals with the plants used by aboriginal tribes of Ratan Mahal and surrounding hills. Some of the important food and medicinal plants restricted to these tribes or this... 相似文献
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A Middle Jurassic dinosaur trackway site from Oxfordshire, UK 总被引:1,自引:0,他引:1
Julia J. Day David B. Norman rew S. Gale Paul Upchurch & H. Philip Powell 《Palaeontology》2004,47(2):319-348
The Middle Jurassic (Bathonian) Ardley trackway site in Oxfordshire, UK is described in detail. The track site is extensive, containing over 40 more-or-less continuous theropod and sauropod trackways preserved together on a single bedding plane with some trackways up to 180 m in length. The trackways display reasonable preservation, with claw marks discernible. Sauropod trackways are by far the most abundant and are representative of taxa that exhibit both narrow and wide-gauge styles of locomotion. Theropod trackways are represented by large tridactyl prints and claw impressions that display exceptionally low pace angulation values during their walking phase. One theropod trackway is unique in that it reveals a gait transition associated with a temporary increase of speed. These dinosaurs were walking over a lime-mud firmground to hardground that was emergent, or locally very shallowly submerged. GPS (Global Positioning Satellite) data reveal that the tracks, preserved during a short time interval, trend in a north-easterly direction. Multi-herding behaviour is suggested for the sauropods of differing size. The discovery of this site adds significantly to our knowledge of the taxonomic composition of Middle Jurassic ecosystems. Evidence concerning locomotor styles employed by saurischian dinosaurs, footprint identification, potential trackmaker, social interactions and observations concerning estimates of Middle Jurassic faunal diversity, as well as aspects of dinosaur locomotor evolution are discussed. 相似文献
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Hong-En Jiang David K. Ferguson Cheng-Sen Li Ye-Ming Cheng 《Review of Palaeobotany and Palynology》2008,150(1-4):37-47
Silicified coniferous wood was collected from the Lanqi Formation (late Middle Jurassic in age) at Shebudaigou Village, Liaoning Province, China. Three taxa are identified, namely Pinoxylon dacotense Knowlton, Xenoxylon phyllocladoides Gothan, and Araucariopitys sp. Based on these new data, and those of other fossil plants reported previously from the same formation, we consider the climate during the deposition of the Lanqi Formation was subtropical, humid and seasonal. In this respect the Lanqi flora differs from the coeval Shimengou and Longmen floras from North China. The Longmen flora was deposited during more humid, subtropical conditions, while the Shimengou Formation indicates that the climate was warm temperate and dry. Our data would suggest that the Late Jurassic climatic pattern was initiated as early as the late Middle Jurassic. 相似文献
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Stable isotope analyses of 61 diagenetically unaltered belemnite rostra from the Middle to Late Jurassic of the Kachchh Basin of western India suggest stable paleotemperatures across the Callovian-Oxfordian boundary (~14°C). Only at the end of the Middle Oxfordian water temperatures drop for more than 3°C before reaching again higher values during the Kimmeridgian (~12.3°C). The data do not support polar glaciations proposed for the Middle to Late Jurassic transition, which necessarily would have led to a global temperature and sea-level minimum at the boundary. Callovian to Oxfordian rocks in the Kachchh Basin point to a gradual shallowing corresponding to a slight fall in relative sea level. However, the magnitude of this regression is comparatively small, and the sea-level minimum is reached in the late Early Oxfordian and not close to the boundary. Results from the Kachchh Basin therefore, imply almost stable climatic conditions during the Middle to Late Jurassic transition and do not show any evidence for polar glaciations. 相似文献
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Julian E. Andrews 《Ichnos》2013,20(4):247-253
The Kilmaluag Formation of the Great Estuarine Group (Middle Jurassic) of Scotland represents deposition of mixed carbonate and clastic sediments in a low‐salinity coastal lagoon to floodplain lake setting. Large, unusual trace fossils occur at two horizons within the formation. One type consists of platelike structures about 50 cm in diameter, which are found on wave‐rippled sandstone. These structures, strikingly similar to burrows produced by modern mudskippers, are assigned to fish that shallowly burrowed into the lagoon‐shore sediment. The second type of burrows, found in brecciated, dolomitic limestones, are pipelike, about 4 to 7 cm in diameter and as much as 50 cm deep. One example has a chamber at the base of the pipe. Although most features of these structures appear similar to modern lungfish burrows, the chamber is most similar to structures produced by modern crayfish. The animal probably burrowed into the moist, mudflat sediment to escape desiccation during seasonal aridity. 相似文献
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陕西子洲县中侏罗统延安组砂岩中,同一地点共厚约1.7 m的5个层面发现4种食肉类恐龙足迹,自上而下分别为:1)第5层面大型三趾型足迹,实雷龙足迹科王氏子洲足迹(新遗迹属、新遗迹种)Zizhoupus wangi ichnogen.et ichnosp,nov.;2)第4和第3层面中型三趾型足迹,实雷龙足迹科龙尾峁张北足迹(新遗迹种)Changpeipus longweimaoensis inchnosp.nov.;3)第2层面小型三趾或四趾型足迹,虚骨龙类小理河陕西足迹(新遗迹种)Shensipus xiaoliheensis inchnosp.nov.;4)第1层面小型三趾型足迹,虚骨龙类的铜川陕西足迹Shensipus tungchuanensis. 相似文献