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1.
苏铁,学名:Cycas rEvoluta Thunb别名:铁树、凤尾蕉、风尾松、避火蕉;常绿乔木,属裸子植物门、苏铁科、苏铁属,原产我国南部,现主要分布在广东、福建、云南、海南、湖南、台湾等长江以南广大地区;雌雄异株,花期5-8月,种子10月成熟. 相似文献
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本文是继中国始苏铁Primocycas chinensis Zhu et Du之后，又报道一种古植物文献未见记载的早二叠世晚期苏铁科小孢子叶球，命名为古生铁花(新属、种)Cycadostrobilus paleozoicus Zhu，gen. et.sp．nov．标本采自我国山西省太原市东山煤矿的下石盒子组，它是世界迄今已知的一种最古老的小孢子叶球化石。和本新属同层发现的化石，除了中国始苏铁之外，还有楔叶Sphenophyllum、齿叶Tingia，楔羊齿Sphenopteris、楔叶羊齿Sphenopteridium、织羊齿Emplectopteris、栉羊齿Pecopteris、大芦孢穗Macrostachya、科达Cordaites、带羊齿Taeniopteris、角籽Cornucarpus和几种也未见记载而形态又非常特殊的植物。本文认为当前报道的古生铁花(新属、种)很可能和中国始苏铁同属一种植物，其营养叶可能是疏脉带羊齿Taeniopteris norinii Halle。 相似文献
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2亿多年前，在古生代的最后一个纪——二叠纪，地球生物圈发生了重大变革和更替；高大的蕨类植物因为无法适应地球气候的变化已趋衰退，古生代植物开始了向中生代植物的过渡。到了中生代，裸子植物成为植物界新一代的统治者，苏铁应势而出，开始在地球上生长繁殖。 相似文献
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运用常规石蜡切片方法，结合显微荧光技术对越南篦齿苏铁Cycas elongata 小孢子发生和花粉个体发育进行了研究。结果表明：其小孢子叶球5月中下旬开始萌动，小孢子囊着生在小孢子叶远轴面，且3-5小孢子囊以辐射状排列方式聚生成聚合囊。小孢子囊壁由6-7层细胞组成，包括表皮、中层及绒毡层。绒毡层来源于成熟造孢组织的外围细胞，其退化形式为分泌型。6月中旬，小孢子母细胞进入减数分裂I，至6月下旬形成四分体。母细胞减数分裂后胞质分裂的方式与其他苏铁类植物不同，具有连续型与同时型两种类型。7月中旬，小孢子经过2次有丝分裂后，形成3细胞的成熟花粉粒。7月下旬进入散粉状态。在花粉发育过程中，母细胞内淀粉粒的积累及其壁上胼胝质的沉积均呈现规律性变化。 相似文献
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苏铁蕨[Brainia insignis(HOOK)J.Sin.]别名赤蕨,是蕨类植物乌毛蕨科,苏铁蕨属单一常绿植物。 苏铁蕨是古生代泥盆纪时代子遗植物,也就是说大约4亿年前,地球上已经出现苏铁蕨植物了。它比恐龙早出现2.05亿年。苏铁蕨经过亿万年地球的变迁而顽强幸存下来,是活着的化石。 相似文献
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This paper reports chromosome number and karyotype analysis of
Cycas panzhihuaensis endemic to China. The material was collected from Dukou, Si-
chuan. It is a diploid species, with 2n=22=2m+4sm+4st+l2t. The karyotype of Cycas
panzhihuaensis is different from that of the other species of the genus Cycas, which
was known to be 2n=4m+8st+10t. The former is a new karyotype in the genus. The
authors briefly discuss karyotype evolution of the genus Cycas in this papar. 相似文献
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eterachopsis was proposed by the senior author as an independent genus of
the family Aspleniaceae in 1940 with 2 species. Since then much study on its morpho-
logy, anatomy, gametophyte and palynology has been carried out by Nayar, Bir, Chan-
dra & Nayar and Chang et al., and they are of the opinion that the genus like Ceterach,
is a comparatively primitive element in the family Aspleniaceae. The queer zigzag pa-
tern of cutting of lanceolate fronds appears extraordinary in the family Aspleniaceae,
and also suggests its antiquity in evolution. So far only 3 species (C. dalhousiae, C.
paucivenosa and C. magnifica) are recognized, the former from W. Himalayas, also
known from Africa, while the latter two from W. S. China (Yunnan). However, in
the past forty years the Chinese botanists have discovered 2 more species as new in N.
W. Yunnan, thus bringing the total known species of the genus up to 5. The present
paper is a brief summary on the genus Ceterachopsis, which will be published in detail
in the Flora Sinica vol. 4.
Pteridologists are also divided in their views regarding the generic status of Cete-
rachopsis with 5 well-defined species in Yunnan and the East Himalayas. We prefer
to mintain it as a genus separate from Asplenium on account of its distinct morpholo-
gical features. It is to be hoped that more species may come to light in the mountainsin N. W. Yunnan through further exploration now under way. 相似文献
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乌蒙杓兰及其近亲种 总被引：1，自引：0，他引：1
陈心启 《中国科学院研究生院学报》1985,23(5):369-375
In addition to describing a new species, Cypripedium wumengense, as well
as a new variety, C. bardolphianum var. zhongdianense, nomenclatural and taxonomic
notes are made on its allies and the division to which they belong. They are ltrge]y
found in the Hengduan Mountains in southwestern China, characterized by the absence
of bract, havirg lip more or less covered with small wart-like outgrowths, and that as
the capsule matures the scape becomes much elongated. Six species of this group have
hitherto been reported, of which, however, C. ebracteatum and C. nutans are regarded
here as conspecific with C. fargesii and C. bardolphianum respectively. Thus, including
the new taxa described here, it composes five species and one variety: C. bardolphianum
W. W. Sm. et Farrer (var. bardolphianum and var. zhongdianense S. C. Chen), C. mic-
ranthum Franch., C. fargesii Franch., C. margaritaceum Franch. and C. wumengense
S. C. Chen. They are all grouped here into the same section, Sect. Trigonopedium
(Franch.) Pfitz., the oldest legitimate name of this group in the rank of section. 相似文献
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库尔班·尼扎木丁 《中国科学院研究生院学报》1984,22(6):466-468
The karyotypes of 3 species of Ceratoides (C. arborescens, C. ewersman-
niana and C. latens) were studied. The results show that C. arborescens is a diploid,
with karyotype formula 2n=2x=18=16m+2sm, C. ewersmanniana is also a diploid, with
2n=2x=18=14m+4sm, while C. latens is a tetraploid, with 2n=4x=36=24m+12sm. Ac-
cording to the karyotypes, the morphological features and geographical distribution, C.
arborescens seems to be a primitive species and it might have originated in northern
China. C. arborescens and C. ewersmanniana are similar to each other, not only in mor-
phology but also in karyotype, which shows that they are closely related and that C. ar-
borescens might be the progenitor of C. ewersmanniana. The karyotypes of the 3 speciesof Ceratoides are basically identical, with only minor differences. 相似文献
17.
In order to get a thorough understanding of the Characeae, the specime-
ns collected from Guangxi and Gansu were identified. The result shows that the
two provinces, especially Guangxi, are abundant in this family. In this paper, ho-
wever, reported are only new species, new varieties and new records of Chara in China.
They are Chara vernicosa sp. nov. C. globularis var. inflata var. nov. and C. howe-ana var. subgymnophylla var. nov., C. brionica stapf and C. calveraensis comb. nov. 相似文献
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One new species Coloniophora shanxiensis Y. J. Ling et S. L. Xie, is described,and one new record, C. spicata (Schmid.) Islam, is reported both from shanxi, China. 相似文献
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