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41.
广东苏铁及中国东南部几种苏铁的研究 总被引:2,自引:0,他引:2
本文对华东南(台湾,广东,海南)产的广东苏铁、台东苏铁及海南苏铁的形态学、解剖学和分类学问题、以及这几种苏铁的亲缘关系进行了讨论。本文附有检索表及图。 相似文献
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Six alkaloids were isolated from the stem of Alseodaphne hainanensis Merr. (Lauraceae) collected in Hainan Island. Four of them were identified as xylopinine, armepavine, doryafranine, and 1-(4-methoxybenzyl)-6,7-methylenedioxy-l,2,3,4-tetrahydroisoquinoline by means of spectral analysis and comparison of physico-chemical constants. 相似文献
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Ruan Yun-Zhen 《植物分类学报:英文版》1988,26(6):443-449
In the classification of J. D. Hooker (1873) and of K. Schumann (1891),
the genus Prismatomeris Thw. is included in the tribe Morindeae of Rubiaceae. In the modern classifications, e. g. Bremekamp (1966), however, the taxonomic position of the genus is
still uncertain. The genus agrees with the tribe Morindeae in the downward radicle, valvate
aestivation of the corolla lobes and presence of raphides, but it differs significantly from the
latter in the free flowers, bilocular ovary and the peltate ovule attached to the upper half of
septum. Therefore, it would be more suitable that the genus is separated from the tribe Morindeae Miq., and is raised to the rank of tribe, placed in the subfamily Rubioideae based on
Bremekamp’s delimitation.
In the present paper ten character pairs of the genus and the notes on their taxonomic
value are presented and two following species are recognized:
1. P. tetrandra (Roxb.) K. Schum. is found in northern India. Its subspecies,
which is distributed in Yunnan of China and in Thailand, was previously called P. tetrandra (Roxb.) K. Schumann, and is now revised as P. tetrandra (Roxb.) K. Schum.
subsp. multiflora (Ridley) Y. Z. Ruan.
2. P. connata Y.Z. Ruan is described as a new species, that has been treated as P.
tetrandra (Roxb.) K. Schum. by previous auth rs. It is native to the subtropic region of South
China. Its tropical new subspecies, P. connata. Y. Z. Ruan subsp. hainanensis Y. Z.
Ruan, is found on Hainan Island. 相似文献
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Tseng Yung-Chien 《植物分类学报:英文版》1985,23(3):225-227
In the present paper the longstanding confusion of three uncertain species of Chloranthus, C. monostachys R. Br., C. pernyanus Solms-Laub. and C. kiangsiensis Metcalf is clarified. In addition to the new record of C. nervosus Coll. et Hemsl. to the flora of China, the distributional ranges of Sarcandra hainanensis (Pei) Swamy et Bailey and Hedyosmum orientale Merr. et Chun are also found to be much bigger than previously known. 相似文献
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阔鳞瘤蕨(水龙骨科)配子体形态发育的研究 总被引:12,自引:0,他引:12
利用光学显微镜详细观察记录了阔鳞瘤蕨孢子萌发、配子体发育及幼孢子体形成的整个形态发育过程。结果表明:成熟孢子黄色,极面观椭圆形,赤道面观肾形,近极单裂缝,表面具大小不一的球形颗粒。接种后6~8 d孢子萌发,萌发类型为书带蕨型,形成3~7个细胞的丝状体。原叶体发育为槲蕨型,接种后30 d左右进入片状体阶段,毛状体出现在片状体形成之后,幼原叶体短舌状,成熟原叶体心脏形。精子器在接种后60 d左右开始产生,颈卵器在精子器发生后10 d左右形成,每个原叶体上只能形成一个受精卵。培养基培养的片状体常在基部进行营养繁殖。 相似文献
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