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Harrington等(1959)指出:"间肋沟是尾肋部从轴沟切过的横沟,表示融合的肋节界线"。Whittington和Kelly(1997)在该书重编时重复使用了这句话。也就是说,间肋沟这个概念只出现在尾部。但在中国的教科书中,尤其是近年来使用的主要古生物学教程中,也把"间肋沟"标注在胸肋之间,意思是胸肋之间不是缝而是沟。但三叶虫肢解时每一胸节是单独分开的,胸节之间是不融合的,只有尾部是一块完整的甲壳,上面才有间肋沟。作者认为,用通用的定义来限定"间肋沟"才更合适。  相似文献   

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林天瑞 《古生物学报》2019,58(4):436-444
通过对我国己经正式发表的Mufushania三叶虫的18个种模式标本的头盖特征进行Q型聚类分析,并结合传统定性分析后,提出其中Mufushania shalangensis Zhang and Zhou inZhang et al.,1980,M.angustilimbata Zhang and Zhou inZhang et al.,1980,和M.kailiensis(Yuan in Yuan et al.,2002)(=Elrathiella kailiensis Zhou in Lu et al.,1974)等3种应从Mufushania属中删除,对余下15个种,通过修订,转移和归并为2个种:M.nankingensis Lin,1965和M.bella(Yuan in Yuan et al.,2002)。本文将对研究我国寒武纪第二世晚期褶颊虫类三叶虫系统演化、生物地理分区以及华北与华南生物地层划分和对比,提供重要依据。  相似文献   

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种子附属物的研究   总被引:1,自引:0,他引:1  
本文研究了桃叶卫矛、东北细辛、东北延胡索、狼毒的种子附属物的结构。以新的分类方法,澄清了假种皮、拟假种皮、种阜、种翅等这些文献上比较混乱的名词。  相似文献   

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THE ONTOGENY OF TRILOBITES   总被引:1,自引:0,他引:1  
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FURTHER REMARKS ON THE 'LEAFLET THEORY' OF THE OVULE   总被引:1,自引:1,他引:0  
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新材料表明定远虫(Tingyuania)和双岛虫(Dinesus)这两个三叶虫属足有效的,前者并不是后者的晚出异名.双岛虫类的地质延限被下延至传统早寒武世晚期的清虚洞组.补允描述首次发现的定远虫的尾部,并描述双岛虫的一新种.  相似文献   

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1. It is suggested that in the assimilation process of green plants the reduction of the CO2 takes place with the help of Fe++ ions (present in the chloroplast) under the influence of light, which is absorbed by a sensitizing chlorophyll-CO2-complex. 2. It seems that the chlorophyll has to fulfill two different functions depending on its situation in the chloroplast. The chlorophyll molecules on the surface of the lipoid phase (in contact with an aqueous phase containing Fe++) combine with CO2 to form a light absorbing chlorophyll-CO2-complex and in this way take part in the reduction of the CO2. The light energy is also absorbed by the greater portion of the chlorophyll, which is dissolved in the interior of the lipoid phase, and eventually handed over to the chlorophyll molecules on the surface. 3. The photosynthetic unit of Emerson and Arnold may be determined by the ratio: See PDF for Equation so that for every chlorophyll molecule on the surface there are about 500 molecules in the interior, which provide it with the necessary quanta.  相似文献   

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Sheng  S. F. 《古生物学报》1958,(2):183-204
INTRODUCTION The materials described here in this paper were collected from three regions (1) in theOmeishan of Szechuan, (2) along the Szechuan-Kweichow border, and (3) in the central Yunnan.Collections from the former two regions were collected by the author in 1938-1940, while fromMr. C. S. Pien and the late Mr. T. Y. Hsu. The trilobite-bearing strata of these regions  相似文献   

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