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2.
尽管一般人不会关心“人从哪里来,将要到哪里去”的问题,但是在涉及这类问题时也不免会很感兴趣。不过,更让人感兴趣的相关问题是：人最像谁？笼统的答案是：人与灵长类最相似。 相似文献
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论文主要从桥面施工的准备工作、施工方法确定、施工工艺安排及技术指标评定等几个关键部位入手，介绍了桥面施工过程。 相似文献
10.
将异枝竹属Metasasa W．T. Lin作为酸竹属Acidosasa C．D．Chu et C．S．Chao ex Keng f．的异名处
理。异枝竹Metasasa carinata W．T. Lin和白环异枝竹 Metasasa albo-farinosa W．T．Lin作为新组合名Aci-dosasa nanunica(McCl．)C．S．Chao et G．Y．Yang，comb．nov．的异名。 相似文献
11.
论禾本科黍亚科的系统分类与演化 总被引：1，自引：0，他引：1
刘亮 《中国科学院研究生院学报》1988,26(1):11-28
Subfam. Panicoideae consists of 230 genera and 3000 species, about 1/3 of the
total number of Gramineae.
The evolution in Gramineae (Poaceae) is considered to have been proceeding in the direc-
tion of simplification. Three major lineages in Panicoideae are recognized based on analysis
of characters, geographical distribution and ecological preferences. They are represented res-
pectively by three supertribes i.e. Panicatae, Andropogonatae and Maydatae. The first supertribe
has well-developed florets, fertile lemma indurate, but is awnless and thus is the primitive
group in the subfamily. In the second supertribe spikelets are well-developed, the lower
glume is larger than the florets and embraces them, the florets are awned. Particularly signi-
ficant is the evolution of spikelets from solitary to paired, from the two spikelets of each pair
both bisexual and alike in form to heterogamous pair of spikelets in which the sessile one is
fertile and the pedicelled one sterile and further to homogamous pair of spikelets at base of
inflorescence. In this lineage occurs an inflorescence protected by a large sheathing bract. It
is the most flourishing by developed evolutionary branch. In the third supertribe raches are
developed, thick, inflorescences have become pillar-shaped with spikelets sunken in the raches.
The reduction of spikelets from bisexual to unisexual has taken place and they occur on se-
parte inflorescenes, bringing about subsequent sexual differentiation of inflorescences. Raches
have also evolved from solitary to united. The supertribe Maydatae is likely to be one of the
most advanced group in Gramineae.
Subfam. Panicoideae occurs in the tropics and subtropics, and these three supertribes have
apparently followed three lines of development under different environmental conditions. The
supertribe Panicatae adapts to hot moist conditions, the supertribe Andropogonatae adapts to
a monsoon climate, occurring in savannas, the supertribe Maydatae occurs in monsoon moist
conditions. 相似文献
12.
向秋云 《中国科学院研究生院学报》1987,25(2):125-131
Cornus L. s. 1. is a large polytypic genus. The classificantion of which has been
so different that some authors recognize several separate genera, while others treat them as ei-
ther subgenera or sections. New evidence from many disciplines such as palynology, cyto-
logy, wood anatomy and embryology supports the view that the genus should remain in the
broad sense. I basically agree with the treatment by Ferguson (1966b) before my finishing
a comprehensive study on Cornus L. s. 1. except for supporting the separation of subgenus
Afrocrania as an independent genus. A new subgenus Sinocornus Q. Y. Xiang, containing
one species, C. chinensis Wangerin, is established here on account of its inflorescence axillary
and different from the other members of the genus which all have terminal inflorescences only.
The inflorescence developed from a terminal bud implicates the sympodial nature of axis of
stem and the one from an axillary bud the monopodial one. It is reasonable to regard the
character as of subgeneric value. Also a new combination, Cornus subgen. Syncarpea (Na-
kai) Q. Y. Xiang, is proposed here as a substitute for Cornus subgen. Benthamia (C. B. Clar-
ke) Schneider used for a long time. Because the valid publication of the former name subgen.
Syncarpea Nakai is earlier than the latter one. The types of inflorescences of 8 subgenera re-
presented by type or selected species are illustrated. 相似文献
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我国小麦族的形态演化与分类、分布的研究 总被引：3，自引：0，他引：3
本文以演化形态为基础，结合地理分布和生境条件，研究了中国小麦族的分类和属
间的亲缘关系。 小麦族的穗状花序可认为由雀麦族的圆锥花序和短柄草族的总状花序演化而来，演化路 线可归纳为：1．圆锥花序的各级花序柄缩短直接形成圆锥穗状花序，具不定数小穗或假单生小穗，其颖与外稃的中线及小穗轴不在同一面上。2．圆锥花序简化为总状花序后小穗柄再缩短，形成简单穗状花序，具真单生小穗，其颖、稃的中线与小穗轴处于同一面上。 3．聚伞圆锥花序简缩为聚伞穗状花序，具三联小穗，其居中小穗的颖位于外稃的背面，侧小穗的颖位于外稃 的侧面。据此，根据小麦族颖、外稃的形态和其它性状、生境、分布，国产的和引种的小麦族植物可分为13个属(赖草属、披碱草属、鹅观草属、偃麦草属、山羊草属、小麦属、冰草属、旱麦草属、黑麦属、簇毛麦属、新麦草属、大麦属和猬草属)，本文主要讨论了它们之间的亲缘关系。 相似文献
15.
Pyrgophyllum (Gagnep.) T. L. Wu et Z. Y. Chen is a monotypic genus of Zingibera-
ceae from China. Originally, it was placed in Kaempferia as a subgenus by Gagnepain (1901),
later transferred to Camptandra by Schumann (1904) and to Caulokaempferia by R. M. Smith.
(1972).
In this paper, the authors suggest that the separation of Pyrgophyllum at generic rank is
justified on cytological, morphological and anatomical evidence. It is characterised by the large
lamina-like bracts, which are rarely seen in Zingiberaceae. The margin of each bract is ad-
nate to the main axis of the inflorescence at the base and the lip is lobed. Trichomes unicel-
lular, stomata each with 4-7 lateral subsidiary cells, lateral veins are of three various types of
vascular bundles: girder-shaped, semigirder-shaped and isolated. The pollen grains are spinecent.
The basic chromosome number (x) is 21.
The type species, Pyrgophyllum yunnanensis (Gagnep.) T. L. Wu et Z. Y. Chen (Kaemp-
feria yunnanensis Gagnep.), is only distributed in Yunnan and Sichuan provinces of China.
相似文献
16.
橐吾属Ligularia Cass．是菊科千里光族款冬亚族的一个大属。在款冬亚族中本属与大吾风草属
Farfugium Lindl．亲缘关系最近，但进化程度较高。本属包括6组，11系129种。所有种类均分布在
亚洲，仅2种扩散至欧洲。在东亚地区有119种，占该属总种数的96％。高度集中在横断山区的有4组、
6系67种，其中61种为特有种，占该属总组数的66％，总系数的54．5％，总种数的52％。这个事实
表明了横断山区是该属的多度中心和多样化中心。通过性状分析，伞房组伞房系Sect．Corymbosae，
Ser．Calthifoliae叶肾形，具掌状叶脉，头状花序大而少，排列呈伞房状，总苞半球形，被认为是该属的
原始类群。原始种齿叶橐吾L. dentata和鹿蹄橐吾L.hodgsonii的分布区从我国四川东部经过湖北、湖
南、安徽、福建等省至日本。这个分布格局与近缘属大吴风草属Farfugium一致。
根据共同起源原理，这两个属的祖先极有可能就发生在这一地区。因此我们推测东亚地区从中国四
川东部至日本这一地区是本属的发源地，然而根据地质历史和现代分布，作者认为中国中部(包括四川
东部)是本属的初始起源地。该属起源后，基本上沿亚洲南缘的山地扩散，少数种类向东北至亚洲东北部。本属起源时间至少不晚于中白垩纪。 相似文献
17.
中国毛茛科植物小志(廿二) 总被引：2，自引：0，他引：2
王文采 《中国科学院研究生院学报》1998,36(2):150-172
(1)揭示了铁线莲属以下演化趋势:萼片由开展到直立;雄蕊由无毛到有毛;雄蕊花丝由条形演
化到披针状条形或倒披针状条形;花药由长圆形演化到条形或狭条形;药隔不突出到在顶端突出;在雄
蕊被毛时,毛由少而短到多而长;此外花序由具花序梗和苞片到花序梗和苞片消失,以及由自当年生枝
叶腋生出转变到自老枝腋芽中生出。主要根据上述演化趋势,本文将我国铁线莲属各组及组下分类群做出新的排列。(2)描述了6新亚组,6新系,2新种,4新变种,给出了5新组合,4新等级和2新名。 相似文献
18.
陈介 《中国科学院研究生院学报》1964,9(1):1-12
The purpose of the present paper is to discuss the systematic position of the genus
Schnabelia originally proposed by H. Handel-Mazzatti in 1921, who considered it as be-
longing to the family Verbenaceae, a point which he further emphasized in 1936. How-
ever, in his paper on the Chinese verbenaceous plants (1932), Prof. Pei Chien thought
the genus should be removed from Verbenaceae into Labiatae and allied it with such
genera as Ajuga and Teucrium on the ground that it also has deeply lobed ovary. Since
then botanists on Chinese plants, such as Prof. Y. Z. Sun, F. C. How, etc. have always
considered Schnabelia Hand.-Mazz. as a genus of Labiatae.
The present writer has recently studied the genus, comparing its morphology of
ovary, calyx lobes, pedicels, pollen grains, etc. with a number of verbenaceous genera,
and comes to the conclusion that the genus should belong to Verbenaceae as H. Handel-
Mazzatti first proposed and that it is closely allied to the genus Caryopteris, especially
C. nepetaefolia (Benth.) Maxim. Moreover, he considers that the deeply lobed ovary
is not at all a good character even for generic separation, for several genera in Ver-
benaceae, such as Caryopteris, Clerodendron, just like Teucrium and Ajuga of Labiatae,
also have deeply lobed ovaries.
From the ample herbarium material, the present writer discovered for the first time
that the genus Schnabelia has two types of flowers, cleistogamous and chasmogamous.
The original founder of the genus did not know this peculiar floral character, as not
mention of it was made in the generic diagnosis. Chienodoxa Sun (1951) proves to be
the present genus, which is based upon the cleistogamous type of flowers of an allied or
perhaps the same species.
相似文献
19.
林镕 《中国科学院研究生院学报》1965,10(1):75-90
The present paper concerns itself with three Composite genera of the tribe Cynareae
(subtribe Carduinae), Vladimiria Ilj., Diplazoptilon Ling and Dolomiaea DC., all ranging
throughout the Sino-himalayan region, These genera have in the past always been as-
sociated with the Eurasiatic genus Jurinea Cass., though there is hardly anything that
can indicate such a relationship. Jurinea, according to the conception of Iljin, is a clearly
deliminated natural genus, while the three genera now in question are all closely allied to
Saussurea DC., being quite remote from Jurinea in the corolla forms, the structure of
receptacle and pappus, and also in the morphology of pollen grains.
Vladimiria was founded by Iljin, based on Jurinea salwinensis Hand.-Mzt. The
genus is a close relative of Saussurea from which it differs chiefly in the usually many
seriate pappus which are composed of scabrous or partly barbellulate bristles. As a re-
sult of our study, a tentative scheme of classification is here proposed, in which Iljin's
original generic concept has been amplified to include a dozen of species previously re-
ferred to Jurinea by Franchet, Diels, Anthony and Handel-Mazzetti from the flora of
south-western China and adjacent countries. Two sections, namely, sect. Sorocephalos
Ling and sect. Vladimiria (Saussurea sect. Carduella Franch., Mazzettia Ilj.), are being
proposed.
Diplazoptilon, a new monotypic genus based upon Jurinea picridifolia Hand.-Mzt.,
is here proposed. It occupies an intermediate position between Vladimiria and Saussurea
with a closer affinity to the former, from both of which it is, however, distinguished
chiefly by the biseriate pappus with equal plumose bristles.
Dolomiaea, a natural genus early founded by De Candolle on the basis of the Hima-
layan D. macrocephala DC., was considered by Bentham and Hooker f. as not different
from Jurinea, a treatment having being followed since by most botanists of the past.
But, as mentioned above, its relationship with Saussurea is obvious. It seems to differ
from that genus in the two to many seriate pappus, consisting of numerous barbellulate
bristles, and in the short style branches. In view of its affinity with Saussurea rather
than with Jurinea, the generic status of Dolomiaea should be maintained accordingly. As
construed above, the genus is now represented by about 5 species, most of which werepreviously referred to Jurinea by different botanists. 相似文献
20.
山茱萸属应予重新确认 总被引：1，自引：0，他引：1
The genus Macrocarpium has been accepted only by a few scholars since
its separation from Cornus L. by T. Nakai in 1909. Bentham, Hooker, Hutchinson and
the others consider that the ovary of Macrocarpium is 2-celled and the genus should be
placed back into Cornus. We have discovered that are generally I-celled. In addition,
Macrocarpium is different from Cornus in basic chromosome number (X), flowering
physiological character, inflorescence type and involucral scale. Thus the genus Ma-crocarpium (Spach) Nakai should be reaffirmed. 相似文献