The present paper first reports the experimental results of Crambe abyssinica introduced from USA and cultivated in China and its somatic chromosome number (2n = 90). After two year selection, it has been found that the oil content of its dehulled seeds in 44.47, about 62.37- 62.50 of which is erucic acid and is 2.5-7.5 higher than previously reported ones. The con-tent ofglucosinolates is 71.51-82.21. ^mol / g. The theoretical yield attains 1485-5250 kg / hm2. Therefore, Crambe abyssinica shows itself a promising oil crop which can be used in industry in China.

A new species, Dryopteris gonggaensis and two new record species of Dryopteris in Sichian are reported in the present paper.

The traditional edible plants ofJinuo Nationality are studied in this paper. The Jinuo is one of the minorities in China who have been practising swidden cultivation (in another word is slash-and-burn agriculture). They cultivate only 54 species of edible crops. Most of their diet is collected from forest lands and swidden fields nearby. Some 179 species of edible plants are re-ported in the present paper, in which 86 species are wild vegetables and 37 species are wild fruits.

In the present paper, two new varieties of Morus ustralis Poir. are described; five new combinations are made, i.e. Morus macroura Miq. var. mawu (Koidz.) C.Y.Wu et Cao, M. cathayana Hemsl. var. gongshanensis (Cao) Cao, M. mongolica (Bur.) Scheid var. barkamensis (S.S.Chang) C.Y.Wu et Cao, M.mongolica (Bur.) Scheid. var. yunnanensis (Koidz.) C.Y.Wu et Cao, M. australis Poir. var. hastifolia (Cao) Cao; M. jinpingensis S.S.Chang and M. mongolica (Bur.) Schneid. var. hopeiensis S.S.Chang et Wu Yu-bi are reduced to synonymy.

Cyrtandromoea Zoll. is a genus finally belonging to Scrophulariaceae and native to Indonesea, Jave and especially Sumatra, West Malaysa, India (Nicobar Island), Thailand, Myanmar. It is new reported from South and Northwest Yunnan province in China. There are two species, one is a new record, the other is a new species.

Distribution of Fagaceae from Tibet has been discussed based on field expedition in Tibet and taxonomical research at present paper. There are 3 genera including 33 species of Fagaceae in Tibet, Castanopsis with 7, Lithocarpus 11, Quercus 15 (subg. Cyclobalanopsis 8). Most of them are concentrated in river gorge area of southeast Tibet particularly, Medog and Nyalam of Himalayas. Castanopsis indica, C. hystrix, C. tribuloides, Lithocarpus collettii and L. xizangensis are dominant elements in vegetation of river gorge area altitude below 2000 meter of southeast Tibet and Q. lanata, Q. kiukiangensis and Q. lamellosa are dominant in the area of southeast Tibet, altitude range from 1800 to 2500 meters. Above 2500 meters in this area Q. aquifolioides is dominant. Floristic elements analysis are also made at present paper. Beech plants in Tibet are divided into 7 kinds of floristic elements. They are tropical India, Himalaya to Indo-China distribution pattern, Indo-China to west Himalayan distribution pattern, Himalayan to Japan distribution pattern, Sino-Himalayan distribution pattern, endemic to east Himalaya, endemic to Tibet and endemic to China distribution. Among of them, tropical India, Himalaya-Indochina, Sino-Himalayan and endemic to east Himalayan are the most abundant.

The floristic characteristics of seed plants in the dry-hot river valley of SW China are (1) diversity in areal-types of plant families, genera and species, (2)striking appearance in endemism and abundance in characteristic species. Based on the analysis of the floristic elements in this area, some conclusions on the nature and origin have been drawn as following: (1) The flo-ra of seed plants in dry-hot river valleys is subtropical nature as a whole; (2) Some floristic ele-ments of the semi-savanna and maquis-like scrub in this area are similar to the Tropical Africa, Tropical Asia and Mediterranea region in their corresponding vegetations; (3) Many plant fami-lies and genera are ancient tropical elements with the origin from Gondwanaland.

Tropical Yunnan is the tropical border area of SE, S & SW Yunnan. This area is the range of tropical rain forests and tropical monsoon forests in Yunnan province now. Its seed plants flora has 4915 species in 1447 genera and 248 families. It is basically tropical in nature but has some obvious transitional characteristics from tropical to subtropical floras, so that it is best to be said as a north variant of tropical flora. After analysing its floristic elements, the eastern part and western part of tropical Yunnan have many differences in the geographical relationship, vicariance, endemism, as well as floristic origin and differentiation. The cause of these differences may be due to their different geological backgrounds. So that it is reasonable to divide these two parts of tropical Yunnan into different regions of palaeotropical kingdom, but the range and boundary of these two floristic regions should be based on the map of idealized vegetation of Yunnan (Wu & Chu, 1987).

Four antitumor annonaceous acetogenins were isolated from seed of Annona glabra Linn, by column chromatography on silica gel. Three of them were identified as cherimolin-2(2), annonin 1(3) and desacetyluvaricin (4) by comparison with literature. One of them is new, with structure elucidated as 4-desoxycherimolin-2(l) by spectroscopic methods.

Two new minor steroidal saponins polyphylloside ni and IV were isolated from the aenal parts of Paris polyphylla var. yunnanensis. On the basis of chemical and spectroscopic ana-lysis, their structures were established as 27-hydroxyl-pennogenin 3-0-[a-L-rhamnopyrano-syl (l-2)][a-L-rhamnopyranosyl (1-4)-a-L-rhamnopyranosyl (1-4)]-/?-D-glucopy-ranoside and 23p, 27-dihydroxyl-pennogenin 3-0-[ a-L-rhamnopyranosyl(l- 2)][a-L-rhamnopyranosyl(l-.4)-a-L-rhamnopyranosyl(l-4)]-^-D-glucopyranoside, respectively .

Gallic acid, (+)catechin, (-)epicatechin, (-)gallocatechin, (-)epigallocatechin, (-)epicatechin 3-0-gallate, (-)epigallocatechin3-0-gallate, theogallin, 1,4,6-tri-O-galloyl-/?-D-glucose, l-0-galloyl-4,6-(-)-hexahydroxydiphenoyl-j8-D-glucose and caffine together a mixture crystal ofrutin and kaempferol-3-rutinoside were isolated from ^ecological tea". This is first detailed chemical report for a kind of green tea prepared by the leaves of Camellia sinensis var. assamica cultivated in the south of Yunnan, China.

Three new triterpenoids named uncargenin A, uncargenin B and uncargenin C, which had structures of 3β, 6β-dihydroxyurs-12, 18(19)-dien-28-oic acid, 3j8-hydroxyurs-5(6), 12, 18(19)-trien-28-oic acid and 3β, 6β, 23-trihydroxyolean-12-en-28-oic acid respectively, and two known triterpenoids were isolated from the ethanol extract of Uncaria rhychophyllo Miq. Jacks by means of column chromatography. Their structures were identified on the basis of spec-tral methods.

Five sesquiterpenoids were isolated from the rhizomes of Hedychium yunnanense Gagnep, namely, cryptomeridiol (1) , α-eudesmo (2) ,β-eudesmol (3) , β-elemol (4) and 4-0-ethyl-cryptomeridiol (5) . (5) is a new compound, whose structure was determined by means of spectroscopic analysis.

In this paper, the pollen of Sargentodoxa, Akebia and Holboellia has been examined by LM, SEM and TEM. The result showed that the pollen of three genera stated above is similar fundamentally in shape, size, aperture type and even sculpture. However, as far as the structure of pollen wall is concerned, Sargentodoxa is different to some extent from those of Akebia and Holboellia by having endexine which consists of a solid and homogeneous (uniform) layer, but the endexine of Akebia and Holboellia consists of an inner lamellar or plate-like unit and an outer sol-id unit. Based on pollen morphology especially the pollen wall ultrastructure and other characters such as fruit and ovular number, the authors support that Sargentodoxa be treated as a separate family Sargentodoxaceae.

The systematic positions of these three genera Pyrenaria, Tutcheria and Parapyrenaria have been studied in this paper based on these data of morphology, embryology, palynology and anatomy.Morphologically, these main characters proposed by former researchers to differentiate these three genera from one another, such as the number of ovules in each locule and the texture of carpodermis, etc. are continually variable so that it is difficult to distinguish them clearly. The high similarity in the shape, structure and germination type of their seed binds them closely to-gether.

The pollen morphology of the genus Cycas from China has been investigated under LM and SEM. The pollen grains are of medium size, with polar axis 26.5-35.7 /^m, and equatorial ax-is 20.6- 26.4 fim in length. In shape they are elliptic or circular on AMB, and boat- or kidney-shaped on equatorial contour, with a single deep and longitudinal furrow reaching from end to end on distal face. The opening or closure of the furrows and pollen shape change when th grains are dry or moistened. The inner surface of the furrows are ofter wringled with strips. The distal surface are smooth or rarely minutely warty while on the opposite face it is perforate of foveolate. The interspecific differences are very obscure, implying a natural group of Cycas. The genus Cycas is similar to other genera ofcycads in pollen morphology. Similar pollen type is found only in the genus Ginkgo. Their pollen resemblence implys that their relationship is possibly closer than cycads with other extant taxa of gymnosperms.

The paper deals with the absorption, distribution and biological cycles of chemical el-ements in L. xylocarpus forest in north side of Ailao Mountain, Yunnan province. The results show that C is the most abundant element in the various plants of the forest community, especially in the trunk of trees. The content of inorganic elements from leaves, branches, roots and trunk graduately declined. The accumulation of chemical elements in the community .are estimated 260 346kg/ hm2, in which the accumulation ofchemical elements in tree layer account for 98.7 of the total. The accumulation of chemical elements in the community decreases in the order of OCa>N>Mg>Al>P>Na>Fe>Mn. C, Ca and N are stored mainly in trunk. Al and Fe are stored mainly in roots.

Pollen grains of 11 species of Lycoris from China were examined under light microscope and scanning electron microscope and those of 6 species of Lycoris were examined under transmis-sion electron microscope. Pollen grains of Lycoris of China are navicular or reniformis, ( 25- 37.5) x (67.5-100) ^m in size, monocolpate. The exine is 2-layered, 1.3-2.5 /wi thick. The character of pollen grains of 11 species differs from each other in ornamentation, formation and width of muri, size of lumins, ratio of length of baculum and caput of pilum etc. The exine reticulate ornamentation under LM and SEM. The ektexine consists of semitectate, columellae and foot-layer under TEM. The ecdexine is very thin.The systematic positions of Lycoris were discussed based on characteristics of pollen grains and other organs.