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991.
黑龙江绥滨-双鸭山地区城子河组的银杏类化石* 总被引:5,自引:0,他引:5
本文描述黑龙江东部双鸭山-绥滨地区城子河组的银杏类化石6属14种(5新种)。多数属于银杏目,包括Ginkgoites baoshanensis sp. nov., G. elegans sp. nov., G.manchuricus(Yabe et Oishi), G. microphyllus sp. nov., G. cf. sibiricus (Heer) Seward, G. subadiantoides sp. nov., G.spp., Sphenobaiera qixingensis Zheng et Zhang, cf. Sph. pulchella (Heer) Florin, Toretzia shunfaensis sp. nov.等;属于茨康目的只Phoenicopsis (Phoenicopsis?) sp.,Ixostrobus heeri Prynada两种。 相似文献
992.
Sha Jin-geng 《古生物学报》1992,(3):309-312
This paper describes three new species of Pisidiidae, Pisidium (P.) zhushutangense, Sphaerium(S.) pyrum and Sphaerium (S.) fujianense, assoeiated with very abundant Plicatounio (P.) naktongensis Kobayashi et Suzuki, Plicatounio (P.) fujianensis Gu et Ma and Trigonioides (T.) quadratus Gu et Ma from the Lower Cretaceous upper Hekou Formation of Zhushutang, Hekou Basin, Ninghhua, Fujian. In Japan, the last two species, Sphaerium (S.) pyrum and Sphaerium (S.) fujianense, or their affinis coexist with each other in the upper Wakino Subgroup, the lower Wakamiya and upper Wakamiya Formations, and the lower Inakura Formation, Yamaji Shale, which very probably can be correlated with the upper Hekou Formation yielding these two species.The distinction between Pisidium and Sphaerium is summarized in Table I. 相似文献
993.
湖南异珊瑚目的新材料——兼论异珊瑚目的构造 总被引:2,自引:0,他引:2
记述了湖南渣渡早石炭世维宪期异珊瑚6属: Hexaphyllia, Pentaphyllia, Haptaphyllia, Heterophyllia, Nodohexaphyllia gen. nov. 及 Nodopentaphyllia gen. nov..根据这些珊瑚的内部构造形态,特别从出芽繁殖幼体的构造形态,对异珊瑚轴管的形成、横板的生长形态、隔壁的生长起点及体壁组成的因素等提出了一些新的见解. 相似文献
994.
长期来,人们认为Lobatannularia heianensis(Kodaira)均是彼此融合的,它与大多数种不同。根据河南济源上石盒子组所发现的大量材料证明,它叶轮中的叶也是不相融合的。 相似文献
995.
辽宁营口金牛山人化石头骨的复原及其主要性状 总被引:4,自引:1,他引:3
本文叙述了辽宁营口金牛山人化石头骨的保存情况、复原过程及其主要性状。从头骨壁之薄、脑量之大、以及其他的形态特征,认为它属于早期智人类型而不是猿人,对它的年代为距今28万年的报道,提出了疑问。 相似文献
996.
Diagnostic ultrasound provides an accurate method for the detection of early pregnancy and embryonic loss in macaque species. A developing gestational sac (GS) may be observed on gestational day (GD) 14-15 with positive identification on GD 16-18. Visualization of the yolk sac, embryo, and developing heart on GD 21-25 confirms pregnancy. Continuous observations during embryogenesis provide useful information when assessing the teratogenic potential of a variety of agents. 相似文献
997.
BJöRN E. E. NEUMAN 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1988,21(2):97-114
Examination of some well-preserved specimens of Silurian rugose corals from Gotland reveals that the following categories of life strategies can be distinguished: ambitopic, liberosessile, fixosessile, rhizosessile and possibly limited vagile. Most solitary rugose corals appear to have been liberosessile and are characterized by initial attachment to a small sediment grain but subsequently becoming recumbent on a soft substrate. Detailed studies of Phaulactis angelini, Holophragma calceoloides, Laccophyllum lindstroemi, Rhegmaphyllum conulus and Rhabdocyclus ocksaroensis n. sp., and comparison with earlier described species, provide some new aspects on different life strategies for solitary corals. 相似文献
998.
999.
《Comptes Rendus Palevol》2016,15(5):453-459
Radiolarians are usually abundant in chert sequences and they have thus been widely used for the biostratigraphy of deep-water sediments. However, there are many difficulties in the correlation of radiolarian biostratigraphic schemes with the standard conodont zones. In this study, 21 radiolarian species were extracted from the Gufeng Formation that crops out in the Luojiaba (LJB) section (western Hubei, China), together with 5 co-occurring conodont species. In this way, it is the first time that the Pseudoalbaillella globosa, Follicucullus monacanthus and F. scholasticus radiolarian zones can be directly correlated with the Jinogondolella nankingensis gracilis, J. aserrata and J. postserrata conodont zones. Accordingly, the 3 radiolarians zones are now firmly correlated with the Roadian to middle Capitanian interval (Middle Permian). 相似文献
1000.
《Comptes Rendus Palevol》2016,15(8):927-940
Although the pika from the Moldovan Kalfa locality (early MN10) — representing the oldest European record of Ochotoninae (the clade derived from Bellatona) — is of crucial importance to understand the earliest history of Ochotona, its taxonomy has remained unclear until now. The paper fills the gap by providing a detailed revision of the type material from Kalfa, originally referred to Proochotona kalfense. The analysis is supported by a direct comparison with type materials of Proochotona eximia, Bellatonoides eroli, and Ochotona ozansoyi, the important early ochotonines of the peri-Paratethyan area. The genus Proochotona is regarded here as a junior subjective synonym of Ochotona. The specie kalfense is confirmed to be valid, undoubtedly belonging to the genus Ochotona. It demonstrates an occurrence of a surprisingly advanced p3 phenotype already present in the pre-Turolian of Europe. At the Holoarctic scale, a detailed synoptic survey and discussion of the fossil record, taxonomy, and phylogeny of the oldest representatives of Ochotoninae are provided. 相似文献