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11.
湖北安陆新的恐龙蛋类型的发现及其意义 总被引:4,自引:1,他引:3
本文记述的恐龙蛋化石标本,采自湖北省江汉盆地公安寨组下部.蛋化石保存完好.在普通光学显微镜和扫描电镜下观察,蛋壳的显微结构完整,清晰可见.根据钙质蛋壳基本结构单位的形态及排列特征,笔者建立了—新属,新种——Dendroolithus wangdianensis gen. et sp. nov.,代表恐龙蛋类一个新科——Dendroolithidae fam. nov.此外,残存的卵壳膜纤维化石的发现,将为进一步研究恐龙蛋卵壳膜的结构和氨基酸组成提供宝贵材料. 相似文献
12.
Ruth A. Sandeman Michael J. Hynes John R.S. Fincham Ian F. Connerton 《Molecular & general genetics : MGG》1991,228(3):445-452
Summary A soybean nodulin cDNA clone (E41) hybrid-selected mRNA for three in vitro translation products with apparent molecular weights of 26 kDa, 25 kDa and 24 kDa. Based on Southern analysis of soybean genomic DNA, combined with mapping and sequencing of genomic clones, we identified four genes that are related to E41, one of which was identified to be the previously characterized N-20 gene. Our data indicate the linkage of three of the genes, of which one is a truncated version and suggest that they originated by gene duplication combined with deletion and conversion. The genes are highly expressed and we postulate that the sequence conservation in the 5 and 3 flanking regions of all four genes, has a functional role in their expression. Hybrid-selected translation products of E41 are not immunoprecipitable with antibody to the soluble fraction of nodules suggesting that they are membrane associated. The N-20 gene, which is a member of this gene subfamily, showed sequence similarity to four previously characterized nodulin genes and a phylogenetic tree is proposed based on the extent of sequence similarity. 相似文献
13.
该文研究的轮藻化石采自尼泊尔中西部阿龙科拉地区的比奈科拉组下段。轮藻化石有Nitellopsis (Tectochara)globula(Madler)Grambast et Soulie-Marsche,Chara molassica Straub,C.gigantofusiformis(Yang),Rantzieniella binaiensis sp.nov.,Gyrogona arungensis sp.nov.和Lychnotharnnuspseudoodea(Berger)Soulie-Marsche等,此轮藻化石植物群属新第三纪,可能为中新世晚期。克里雅群轮藻的研究将增添南亚新第三纪地质生态研究的内容。 相似文献
14.
NEW MURID RODENTS FROM THE LATE CENOZOIC OF YUSHE BASIN, SHANXI 总被引:8,自引:8,他引:0
Lawrence J.Flynn 《古脊椎动物学报》1992,(1)
<正> As scientific collaborators of the Chinese-American joint project "Neogene Rocks and Faunas, Yushe Basin, Shanxi, PRC", the present authors, with William R. Downs, Northern Arizona University, sampled the Yushe microfauna in the fall of 1987 and 1988. The fossil temains were retrieved by surface collection and by wet-sieving bulk quantities of sediment. 相似文献
15.
本文记述石龙子类 Scincomorpha 蜥蜴的—新属,甘肃拟贝氏蜥 Mimobefklesisaurus gansuensis gen. et sp. nov. 化石发现于甘肃省肃北县马宗山区晚侏罗世的赤金堡群.这是石龙子类化石在我国的第一次发现,也是目前所发现的这类动物在亚洲的最早的代表. 相似文献
16.
本文对扁头中国短头鲵(新属新种) (Sinobrachyops placenticephalus gen. et sp. nov.) 的形态特征和分类位置进行简述.标本得自著名的恐龙化石产地——自贡大山铺,产出时代为中侏罗世.中国短头鲵是目前迷齿类中在地史上最年轻的一个属.它的发现使迷齿类在地球上生存时代的上限推移到中侏罗世. 相似文献
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19.
DIANE KERMACK 《Zoological Journal of the Linnean Society》1984,82(1-2):101-117
New prosauropod material from a cave filling of Upper Triassic/Lower Jurassic age in Pant-y-ffynnon Quarry, South Wales, is described. The Panl-y-ffynnon fauna also includes thecodont, coelurosaur, crocodile and lepidosaur material.
Most of the prosauropod skeleton is represented. An almost complete but disarticulated skull is preserved. The skull and whole skeleton of the prosauropod are reconstructed. Evidence from the size and relative proportions of the bones, also the state of ossification, indicates that the prosauropod remains represent juveniles.
The level of the jaw articulation combined with the form of the teeth would suggest that the Pant-y-ffynnon prosauropod was omnivorous.
The Pant-y-ffynnon prosauropod resembles closely the much less complete Durdham Down (Bristol) remains of Thecodonlosaurus antiquus Morris; the Welsh material could well be juveniles of that species. Here the Pant-y-ffynnon material is ascribed to Thecodonlosaurus sp.
The mode of deposition of the fossil material is discussed, to account for the deposit containing only juveniles of the prosauropod. 相似文献
Most of the prosauropod skeleton is represented. An almost complete but disarticulated skull is preserved. The skull and whole skeleton of the prosauropod are reconstructed. Evidence from the size and relative proportions of the bones, also the state of ossification, indicates that the prosauropod remains represent juveniles.
The level of the jaw articulation combined with the form of the teeth would suggest that the Pant-y-ffynnon prosauropod was omnivorous.
The Pant-y-ffynnon prosauropod resembles closely the much less complete Durdham Down (Bristol) remains of Thecodonlosaurus antiquus Morris; the Welsh material could well be juveniles of that species. Here the Pant-y-ffynnon material is ascribed to Thecodonlosaurus sp.
The mode of deposition of the fossil material is discussed, to account for the deposit containing only juveniles of the prosauropod. 相似文献
20.
云南开远新发现的腊玛古猿化石 总被引:2,自引:0,他引:2
本文描述的标本是1980年6月和1982年5月,在云南开远小龙潭晚中新世褐煤层中发现的古猿化石。标本有左下第一至第三臼齿列和一件带十二枚牙齿的上颌骨。从标本反映的形态特征观察,应归为腊玛古猿。 相似文献