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通过刺激——反映（S-R）联结,每个人在学习历程中建立起一系列习得性的对自身行之有效的学习策略和学习习惯。作为教师,针对学生不同学习类型的认识,可以更好的引导学生,帮助他们认识自己,发掘自身潜质,形成自己独创性的良好学习习惯,从而极大的发挥其主观能动性。 相似文献
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The present paper is an attempt to throw some light on two Composite genera,
Cavea W. W. Smith et Small and Nannoglottis Maxim., of which the generic features
and the systematic position were heretofore rather badly known.
Cavea, a monotypic genus based upon Saussurea salwinensis Drumm., was described
by W. W. Smith and Small as monocious. From the ample material now in our com-
mand, it is found that the genus is either monocious and dioecious, the capitula in the
latter case being homogamous. The individuals exclusively provided with sterile flowers
are usually smaller in size, sometimes even stemless. Such repartition of sexes was
known in the subtribe Plucheinae (tribe Inuleae), to which W. W. Smith and Small were
correct to ascribe their genus.
Nannoglottis was considered by Maximovicz as un abnormal genus of the tribe
Inuleae, having heterogamous capitula with one series of peripheric fertile ligulate pistil-
late flowers. Having examined the type specimen of N. carpesioices Maxim. and the ex-
tensive collection from Kansu and Tsinghai, we incline to say that the genetic characters
as discerned by Maximovicz are doubtlessly due to his inaccurate observation. The
flowers of Nannoglottis are in fact trimorphous, of which the pistillate ones are 2-3-
seriate, the outer being shortly ligulate and the inner, short-tubulate with truncate apex.
Handel-Mazzetti, much later, indicated that, in another species, the pistillate flowers are
2-3-seriate, but no mention was made about the inner tubulate pistillate flowers.
Franchet, appearing to be unware of Maximovicz's genus, founded his Stereosanthus
Franch. and considered it as a genus intermediate between the tribes Inuleae and Sene-
cioneae. The genus was misinterpreted by Franchet as having dimorphous flowers, the
pistillate ones being all ligulate. Curious enough, one of the major generic features, viz.,
the presence of inner tubulate pistillate flowers, was neglected by all early botanists and
was first recognized by Handel-Mazzetti fourty years later.
However, Handel-Mazzetti was still unacquainted with the characters of Nannoglot-
tis and proposed therefore his new genus Vierhapperia Hand.-Mzt. on the reason that the
flowers are trimorphous. Moreover, he compared his genus with Conyza L. and Erigeron
L. of the tribe Astereae, but the characters marked by him appear not to be different
from those of Nannoglottis.
From the above morphological comparaison, it is evident that Nannoglottis and two
other genera in question possess in common important characters in the general appea-
rance, the flower-forms and the structure of achenes and pappus. The differences in the
disposition of involucral bracts and the length of ligules are criteria good for separating
species, but can hardly be regarded as sufficient for generic delimitation. Moreover,
these three genera are almost similar in their geographical distribution. These points are
adequate to warrant that Stereosanthus and Vierhapperia are in reality congeneric with
Nannoglottis.
Nannoglottis appears to have been correctly placed by Hoffmann in the subtribe
Senecioninae (tribe Senecioneae) though in that subtribe it finds no close relatives. On
account of the outstanding characters of the genus, a further study of its systematic posi-
tion is required.
The present paper is brought to close by a tentative scheme of classification of the
genus so amplified, of which two sections, namely, sect. Stenolepis Ling et Y. L. Chen
(Stereosanthus Franch., p. p. min.) and sect. Nannoglottis (Stereosanthus Franch., p. p.maxim.; Vierhapperia Hand.-Mzt.), altogether including 9 species, are being proposed. 相似文献
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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
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王铸豪 《中国科学院研究生院学报》1965,10(2):121-130
The object of this paper is to deal with the taxonomical problems of the family
Aspidiaceae from the mainland of Asia. In recent years I have had the opportunity to
study copious materials of the family from this region, and recognized the following nine
genera, namely, Lastreopsis Ching, Ctenitis C. Chr., Ctenitopsis Ching, Pleocnemia Presl,
Arcypteris Underw., Tectaria Cavanilles, Quercifilix Cop., Hemigramma Christ and
Pteridrys C. Chr. et Ching.
The members of this family are middle-sized, terrestrial ferns; rhizome erect or sub-
erect, dictyostelic, scaly; leaves tufted, generally uniform, simple pinnate to tripinnatifid;
veins free or anastomosing, forming areoles with or without free included veinlets; rachis
and costa raised on the upper surface, and, as a rule, covered with pale brown multi-
cellular articulate hairs (ctenitis-hairs); sori round or in a few cases acrostichoid; indusia
reniform, or in some genera absent; spores bilateral with perispore.
Dryopteridaceae and Lomariopsidaceae are closely related to Aspidiaceae, and both
were placed in the latter family by the fern students in the past. The main differences
of Dryopteridaceae from Aspidiaceae are: leaves pale green when dried; costa and costule
grooved and free from articulate hairs (ctenitis-hairs) on the upper side; veins free or
very rarely anastomosing (venatio cyrtomii). In general appearance the genus Ctenitis
of Aspidiaceae is very similar to the bipinnate species of Dryopteridaceae, such as
Dryopteris filix-mas (Linn.) Schott, but its costa and costule are raised and covered by
ctenitis-hairs on the upper side, and the leaves turning dull brown when dried, so that
it has no difficulty in distinguishing the genus from the true Dryopteris. The recognition
of the free-veined Ctenitis and its allies as the primitive tectarioid ferns is very important
in delimiting both Aspidiaceae and Dryopteridaceae, which were all mixed up in the past.
Moreover, from the standpoint of plant geography, these two families are also distinct,
for the Dryopteridaceae are mainly ferns of the temperate regions and the mountains in
subtropics in the Northern Hemisphere, but the Aspidiaceae are pantropical by origin.
The chief differences of Lomariopsidaceae from the Aspidiaceae are: rhizome creeping or
high-climbing; leaves strongly dimorphous, free from the ctenitis-hairs; sori acrostichoid.
That Holttum has made Aspidiaceae a subfamily Tectarioideae of the family
Dennstaedtiaceae proves to be very unnatural, because there is hardly any affinity be-
tween the two families; while Aspidiaceae of Copeland is a terrible mixture of Thely-
pteridaceae, Athyriaceae, Dryopteridaceae and Aspidiaceae (sen. strict.) and a few other
families, for even he himself admitted that no one can use the definition to identify any
unknown members of his family.
Finally, I feel grateful to my teacher, Professor R. C. Ching, for his constant encou-
ragement and warm guidance received both in the course of my study and in the prepara-tion of the present paper. 相似文献
15.
本文对蓝钟花属Cyananthus及整个狭义的桔梗科Campanulaceae(s．str.)的花粉、
染色体和形态性状作了深入的系统研究，表明蓝钟花属是该科的最原始类群，它的亲缘属有党
参属Codonopsis和细钟花属Leptocodon。 对蓝钟花属中各个种及它的亲缘属的地理分布分
析，揭示了该属是典型的中国-喜马拉雅区系的成分，横断山地区是该属的频度和多样性中心；
认为中国西南部及其邻近地区至少是桔梗科原始属的保留中心，甚至可能是该科的起源中心。
作者最后对蓝钟花属各个种的性状作了生物统计分析，在此基础上对全属进行了全面的分类
修订，把原有的26个种9个变种归并为19种(包括2亚种)；对该属的次级分类也作了修订。
首次报道了该属的染色体数目和细钟花属的花粉形态。 相似文献
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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
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小檗科八角莲属和桃儿七属(新属)的研究 总被引：1，自引：0，他引：1
应俊生 《中国科学院研究生院学报》1979,17(1):15-23
1. A classification is made on seven species of the genus Dysosma, of which four
are proposed as new combinations, and one as new species.
2. The pollens of six species in the genus Dysosma and two species of Podophyl-
lum are examined. Morphologically, the Asiatic. P. emodi is radically distinct from the
North American P. peltatum and can be separated from Podophyllum as an indepen-
dent genus-Sinopodophyllum.
3. The trend of evolution in Dysosma (fig. 2)and its relationships with the
genera Sinopodophyllum and podophyllum are discussed.
4. Based on the evidence from an analysis of the ecology and geographical
distribution of the component species (fig. 3), the problem of the centre of develop-
ment of the genus Dysosma has been discussed.
相似文献
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石铸 《中国科学院研究生院学报》1979,17(4):61-71
The present paper is an attempt to propose a preliminary taxomomic treatment of
the genus Hippolytia Poljak. and to analyse the geographical distribution of its com-
posite elements.
This small genus with 17 species is divided into 2 sections, namely, section
Anthodesma Shih and section Hippolytia. Anthodesma is a small section with 3 species
and is characterized by fascicled corymbs, campanulate and nitid involucres, rigidly
herbaceous phyllaries, and undershrubs, while Hippolytia consisting of 14 species is
characterized by corymbose inflorescence or glomerules or compund heads, cuneate and
unpolished involucres, herbaceous phyllaries with pitch black margines.
There are 12 species of Hippolytia in China, of which 3 are proposed as new in the
present paper.
Regarding the distribution pattern of Hippolytia, it is noteworthy to note that its
range of distribution forms a more or less U-shape as shown in map 2. It may be seen
that Hippolytia distributes in Central Asia-Sino-Himalaya-Median Asia. Section Antho-
desma Shih occurs in central Asia, while section Hippolytia in the whole Himalayan
region and northern Meridional Ranges and Median Asia.
There seems to be no center of species concentration within the total range of
Hippolytia, whose species are localized in distribution, for example, H. desmantha Shih
is known only from Qinghai provence (Yu-Shu-Hsien), H. alashanensis (Ling) Shih
is restricted to Ninghsia and central part of Kansu provence. It is interesting to note
that H. yunnanensis (J. F. Jeffrey) Shih and H. longifolia (Wall.) Shih are referred
to as vicarious species. The localization of the species distribution and the obvious
discontinuity of morphological characters between species indicate a remarkable geogra-
phical influence on the species formation of Hippolytia.
Hippolytia is an alpine genus of temperate zone of Asia, in which 64 per cent of
species occurs at high elevations of above 3300m. altitude, 30 per cent of species are
distributed in middle elevations of above 2200m. altitude. The life forms are micro-
undershrubs, erect perennial herbs, glomerule stemless herbs or stemless herbs. It is very
possible that its geographical origin and development may be linked up with occurance
of desert steppe, especially of alpine meadow vegetations in the northern temperate
zone of Asia.
With regard to the geographical elements to which each species of Hippolytia
belongs, it seems to indicate that H. trifida (Turcz.) Poljak., H. alashanensis (Ling)
Shih and H. desmantha Shih belong to the geographical elements of central Asia,
while H. yunnanensis (J. F. Jeffrey) Shih, H. glomerata Shih, H. tomentosa (DC.)
Tzvel., H. senecionis (Bess.) Poljak. H. longifolia (Wall.) Shih, H. kennedayi (Dunn)
Ling, H. syncalathiformis Shih, H. gossypina (Hook. f. et Thoms.) Shih and H. nana
(C. B. Clarke) Shih to Himalayan elements, and H. darvasica (C. Winkl.) Poljak., H.
megacephala (Rupr.) Poljak,, H. herderi (Rgl. et Schmalh.) Poljak. to Median Asia, H.
delavayi (W. W. Smith) Shih to North-West-Yunna.
相似文献
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柳叶芹与当归属和山芹属在花形态、果实结构和花粉特征等方面有较大差异，将本种作为单种属柳叶芹属来处理是合适的。 相似文献
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从露蕊乌头全草中分离及鉴定出4种二萜生物碱： talatizamine, 14-acetyltalatizamine，condelphine 及 isotalatizamine。根据现有的植化资料，其系统位置似更接近于林地乌头及塔拉斯乌头。 相似文献