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131.
Widespread non-marine Mesozoic deposits in China often contain abundant cupedomorpha fossils with significance for correlation. Based on the composition and characteristics of the cupedomorphs, at present, seven cupedid and ommatid assemblages are recognized from the Jurassic-Cretaceous rocks, of which three cupedid and two ommatid assemblages were recovered from North and northeast China: Middle Jurassic Tetrocupes-Hebeicupes cupedid assemblage from northern Hebei and Inner Mongolia (Yanliao fauna); Late Jurassic or Early Cretaceous Ovatocupes-Priacma cupedid and Amblomma-Sinocupes ommatid assemblages from western Liaoning (Jehol fauna); Early Cretaceous Lupicupes-Diluticupes cupedid and Monticupes ommatid assemblages from Beijing and adjacent areas. Both the Ovatocupes-Priacma and AmblommaSinocupes assemblages are important elements of the Jehol entomofauna. Remaining are the Late Jurassic or Early Cretaceous MesotricupesGansucupes cupedid assemblage from Jiuquan Basin, Gansu Province, NW China and the ForticupesPicticupes ommatid assemblage from Shandong Province. In southern China only one poorly preserved ommatid specimen, Zygadenia (=Notocupes) sp. occurs.  相似文献   
132.
本文报道了在湖南新化至涟源早石炭世大塘阶,这一重要舍煤地层中所发现的葛万藻属Girvanella的两个种。它们是杜切葛万藻G.ducii和中华葛万藻G.sinensis。这些化石的发现说明该区域葛万藻化石产出的层位,其沉积环境可能是海水较浅、清静、水动力小的低能环境;其沉积位置可能是在相当于陆棚上部的地方。本文还就葛万藻属的分类标准问题进行了讨论。  相似文献   
133.
本文描述了产于贵阳乌当下奥陶统湄潭组双壳类化石10个种及未定种,其中2个新种。该双壳类化石群落层位低,数量多,为我省之冠,对其研究有重要的意义。  相似文献   
134.
哺乳动物进化是生物进化的重要组成部分之一,是生物进化论、动物学研究的重要内容之一。根据古生物学、现代生物学、生物进化论研究成就,就哺乳动物确定、起源、翼手目进化、水栖哺乳动物进化中的模糊问题进行了分析思考。  相似文献   
135.
研制一种易于施工和保存、环境友好、透明性佳的恐龙化石保护新材料.与传统保护材料(硝基清漆)的对比表明:涂覆传统保护材料的围岩吸水质量分数为1.91%,而涂覆新型保护材料的吸水质量分数为1.42%,后者能进一步阻止水分的渗入,提高化石疏水性.用0.5%H2SO4浸泡,传统材料的起泡时间为48 h,新型材料为96 h;经0.5%pH3的NaCl溶液盐雾腐蚀,传统材料经4 h起泡,新型材料40 h才起泡,表明新型保护材料具有良好耐蚀性.实验中两种材料附着力均为1级,而新型材料的柔韧性为1 mm,优于传统材料的3mm,因而与化石基体间的结合性更好.新型材料具有30 d的紫外老化性能,优于传统材料的10 d.  相似文献   
136.
The origin of arthropods has long been one ofthe most hotly-debated subjects. Arthropods used to bethought closely related with annelids, but the two groups arenow believed to be separated into two major realms withinProtostomia on the basis of new molecular data. Although itis generally held by paleontologists that arthropods should berooted in the early lobopods-.a kind of worm-like creaturewith non-segmented legs, no intermediate forms have beenfound to bridge them. Here we report an organism with amixture of characters, including features characteristic ofarthropods (e.g., primary cephalization with paired eyes,paired antennae, and preliminary tagmosis) and of lobopods(e.g., worm-like body design, the dorsal spines, andnon-segmented limbs or lobe-like legs). The discovery of therare transitional form may throw new light on the origin ofarthropods and suggests that the most primitive arthropodsbegan with paired uniramous legs and the biramous onesevolved later.  相似文献   
137.
The Chengjiang fauna has played a pivotal role in our understanding of the origin and diversification of metazoans since its discovery in 1984. To date, this fauna has been documented as consisting of 121 genera with 140 species belonging to 24 phyla[1-27]. The geo- graphic distribution of the Chengjiang fauna has been expanded from Chengjiang County to eastern Yunnan Province including Haikou, Malong, Yiliang, Anning and elsewhere[25-33], with about 20 localities in to- tal[25,33]. Succes…  相似文献   
138.
Mesozoic to Cenozoic petrified woods are very rich and well preserved in the Khorat Plateau, Northeast Thailand, serving as remarkable material for investigations of tropical vegetation history, paleoclimatic evolution, and paleoenvironmental changes. Our recent field survey and investigations have defined about 50 species of fossil wood assigned to 19 genera and 11 families from Mesozoic to Cenozoic deposits in this region. These woods are ascribed to two groups, gymnosperms and angiosperms. Among them, about 20 species assigned to 7 genera and 5 families are the first reports of the taxa in Thailand. The fossil wood floras indicate that during the late Mesozoic period, the tropical conifer vegetation in Northeast Thailand was dominated by the family Araucariaceae. From the Miocene to Pleistocene, a tropical climate prevailed in this region with perhaps both deciduous and evergreen broadleaf forests comprising the vegetation.  相似文献   
139.
关于文物犯罪几个问题的思考   总被引:1,自引:0,他引:1  
我国《文物保护法》及文博学界将文物视为人类制造物或者与人类活动有关的遗物遗迹。这种界定的不足在于它同刑法的规定不甚协调。走私文物罪的对象应包括古人类化石和古脊椎动物化石,倒卖文物罪的对象不限于珍贵文物,盗掘古文化遗址、古墓葬是单一的行为。在涉嫌文物犯罪中,被委派作鉴定的专家应来自与文物行政部门无隶属关系的高等院校或研究机构。  相似文献   
140.
Based on more exquisitely preserved specimens of Markuelia hunanensis recently recovered from Middle and Upper Cambrian in western Hunan and in the light of Synchrotron radiation X-ray tomo-graphic microscopy, the developmental sequence from cleavage through organogenesis to the pre-hatching of Cambrian embryo Markuelia, especially the developmental sequence during the pre-hatching stage, i.e. from the earliest period when the scalids and tail spines only took shape to the latest period (just about hatching), is established. This developmental sequence provides a pattern of embryonic development during the pre-hatching stage, which has not been established in the living scalidophorans (priapulids, loriciferans and kinorhynchs). Thus, it not only enriches our knowledge on the embryonic development of the extant descendants of Markuelia, but also opens a new window to the evolution and development of the animal.  相似文献   
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