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《科学．经济．社会》1988,(6)
改变甘肃落后面貌的基本思路························································……”··……贾志杰(1·1)领导与决策··························································································……冯之凌(5·257) ·论坛·构想与实践······················································… 相似文献
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《科学．经济．社会》1989,(6)
关于建设黄河上游经济开发试验小区的若干间题·············,··································……贾志杰(1.1)·论坛·论生产力标准与思想政治工作························“···········································……庞道沐(3.129)宜新认识以农业为基础的战略地位···················”··········································……吴… 相似文献
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马毓泉 《中国科学院研究生院学报》1951,1(1):5-19
Gentiana was originally proposed by Tournefort in 1700. Linnaeus adopted this generic name in his “Genera Plantarum” published in 1737. He divided the genus into seven groups on the basis of different shapes of corolla and forms of floral appendages. In his “Species Plantarum” he reorganized them into three artificial ones. Forty years later, Moench established a new genus, Gentianella under which he described G. tetrandra as the type of his new genus. In the view of identity of Gentianella tetrandra with Gentiana campestris L., it is evident that Gentianella represents only some plants formerly included in Gentiana at Linnaeus time. In 1796, Froelich’s monograph on Gentiana appeared. In his work four sections were represented and one of them was Crossopetalum. In 1845, Grisebach also published a monograph of Gentianaceae and recorded fifteen sections of which Amarella and Imaicola are two of his seven proposed ones. In 1888, Huxley studied the floral structure of Gentianaceae in relation with pollination mechanism and, accordingly, divided the family into two main groups, one with epipetalous glands, the other with glands at the base of the ovary. In each group, four types of flowers were found. He concluded that Gentiana was a complex genus on account of presence of four different types of flowers in this group, and suggested that many species of the genus should be separated out to form some smaller generic categories. Six years after, Kusnezow in his monograph divided Gentiana into two subgenera Eugentiana and Gentianella. In his system, subgenus Eugentiana consists of ten sections and the Gentianella, seven. He contributed much to the systematic treatment of Eugnetiana but little to that of Gentianella. He maintained the genus Gentiana in a broad sense. With increased knowledge of this group in the last thirty years, a number of botanists were able to make a clearer delimitation of true Gentiana and its allies and treated them in more natural way. Moench’s genus Gentianella was rerised. In 1936, H. Smith separated Megacodon from Gentianella as a genus. In the present paper, the writer suggests a generic name Gentianopsis for the section Crossopetalum in the same Genus.
This new genus is characterized by (1) its large and somewhat flattened ellipsoidal flower bud, (2) two dissimilar pairs of calyx lobes which are distichously imbricate in aestivation, (3) four triangular, ciflated intracalyx membranes at the base of and alternate with the calyx lobes, (4) distinct gynophore and (5) enlarged stigma. While in typical Gentianella represented by section Amarella, the flower buds are small and terete, a laciniate corona is usually present, and the calyx-lobes are leafy, lanceolate, imbricate, and not provided with intracalyx membrane.
Besides the morphological characters mentioned above, the anatomical structure of
the floral parts is also a significant generic criterion. In Gentianopsis, eight vascular
bundles are present in calyx, representing four dorsals and four fused ventrals. In each
corolla-lobe there are five bundles. In the body of ovary six bundles are present. The
ovule bearing surface is extensive covering nearly to entire surface of the ovary wall with
the exception of a narrow longitudinal zone along the dorsal bundle. In Gentianella,
calyx bundles are three in each lobe, without fusion of the ventrals. In each corolla-
lobe, the bundles are three instead of five as in Gentianopsis but the lateral ones branch
once dichotomously after entering the base of corolla. In the body of ovary only four
main bundles are present due to the fusion of smaller ventral ones. The placentation
is confined to the region of the ventral bundles.
Phylogenetically Gentianopsis and Gentianella may be regarded as closely reIated
and may represent branches of a common line with Gentianopsis standing at a lower
level, Gentianella being more advanced. In Gentianella the number of bundles in the
corolla segments and ovary wall are reduced by partial or complete fusion and the
distribution of ovules is confined only to the region of the ventral bundles. However,
in the calyx of Gentianopsis there is fusion of ventral bundles, whereas the correspound-
ing bundles in the Gentianella remain separate. The Gentianopsis-Gentianella line on
the one hand and the Gentiana line on the other may come again from a common
acestral stock. Gentiana possesses only three bundles in each corolla-lobe. A variety
of plicate between corolla lobes except in case of Gentiana lutea and intracalyx membrane
above the throat of calyx-tube are also the common structures in Gentiana. Thus the
pollination mechanism is highly specialized in the genus. As far as we know, in
Gentiana the glandular appendages usually exist at the base of ovary. If those nectarial
processes are correctly interpreted as the representatives of staminodes, gentiana would,
undoubtedly, be derived from an ancestral form with hypogynous diplostemonous
androecium, and bears no direct relationship to Gentianopsis or Gentianella in which the
glands are epipetalous. It may be reasonable to conclude the Gentiana and Gentianopsis-
Gentianella line are two parallel derivatives from a common ancestor which has the
floral characters of two series of hypogynous stamens. Gentianopsis and Gentianella may
represent branches of a common line with Gentianopsis standing at a lower level,
Gentianella being more advanced. Their relations may be diagrammed below:
Gentianopsis
Gentianella
Common ancestor
Gentiana
This new genus consists of fourteen species and two varieties in the world. Onlyeight species and two varieties are represented in China. They are G. barbara, G. barbatavar. sinensis, G. grandis, G. scabromanginata, G. paludosa, G. nana, G. longistyla,G. lutea, G. contorta, and G. contorta var. Wui. The species of present genus occur in the alpine regions of North Hemisphere. InChina t,hey are distributed in Kokonor, Kansu, Shensi, Shansi, Chahar, Hopei, Manchuria,Hupeh, Szechuan, Sikang, Tibet, and Yunnan. G. Yabei (Takeda et Hara) is foundin Japan, G. detonsa (Bott&) in North Europe, G. ciliata (Linn.) in South Europe,G. crinita (Froel.) G. procera (Holm.) and G. degans (A. Nels) in North America.G. barbata is the most widespreading species and reported in Sibiria and China.G. contorta (Royle) is a common plant in Himalayan mountaineous range, China andNorth part of India. The species and varieties cited in this paper are as follows:
t. Gentianopsis barbata (Froel.) comb. nov.
la. Gentianopsis barbata (Froel.) var. sinensis, var. nov.
2. Gentian opsis grandis (H. Sm.) comb. nov.
3. Gentianopsis scabromarginata (H. Sm.) comb. nov.
4. Gcntianopsis paludosa (Munro) comb. nov.
5. Gentianopsis nana sp. nov.
6. Gentianopsis longistyla, sp. nov.
7. Gentianopsis lutea, sp. nov. 相似文献
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《科学．经济．社会》1992,(4)
二,·大胆推进改革开放加快甘肃省经济建设步伐顾金池(2·1)·专论·江河开发治理与经济发展·············································……江建敏白卫星(1·1)完整准确地理解邓小平改革开放思想的儿个问题···························……徐洋(2·6)上海浦东新区高新技术创业发展构想··········································……肖元真(3·1)关于扩大对外开放与搞活国营大中型企业的几个问题·······… 相似文献
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《科学．经济．社会》1990,(6)
牢固树立持续稳定协调发展经济的指导思想本刊编排部(1·1) ·论坛·我月西北太阳能资源的开发利用展望····························································……黄河上游的一支“火炬’ ·专论·我国边缘地带的社会文化现象与生态经济学分析·································……张维祥关于城市科技、社会协调发展的思考·······················……””””’‘”””””’‘”’‘””‘””’‘在抬… 相似文献
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