Abstract As a continution of our chemical studies on Chinese Paris polyphylla, the present paper deal with the isolation and structural elucidation of three saponins from the aerial parts of Paris polyphylla var. yunnanensis (Fr.) H-M. It was collected from Yunnan, China.

Abstract From the roots of Peucedanum decumbens Mexiam (Umbelliferae), a new coumarin decumbensol (1) was isolated and the structure was established as cis-2' - (1"-methyl, 1"-sencioyloxy-ethyl) -3' -hydroxy linear-dihydr-furanocoumarin by spectroscopic evidence. Five known coumarins, angenomalin( 2 ),columbianadin (3), bergapten( 4 ), umbelliferone( 5 ) and nodakenin( 7 ) were isolated together with ferulic acid(6), stearic acid, lignoceric acid, β-sitosterol and γ-sitosterol.

Abstract Two new steroidal alkaloid glycosides were isolated from Pachysandra axillaris Franch. The structures have been elucidated as 20α-dimethylamino-3-0-β-D-glucopyranosyl-5α-pregnanol and 20α-dimethylamino- 3 -0-β-D-glucopyranosyl -5 (6 )-pregnenol for pachyaxioside A, B; respectively by means of spectroscopic analysis (IR, 1H NMR, 13C NMR and MS).

Abstract Calli derived from young inflorescences of indica rice were placed in MS liquid medium supplemented with 1-7 mg/l 2,4-D snd 5 coconut milk and developed into small embryogenic clusters which were consisted of small, round and thin-walled cells with dense cytoplasm containing starch granules, but small or no vacuoles. when the clusters were transferred to MS agar medium supplemented with 1 mg/l BA, some were found at globular-, heart-, pear-shaped and mature embyo stages by scanning electromicroscope, and the embryoids germinated into intact plantlets after two weeks. 10-to 14-day old suspension cultures had higher capacity to regenerate plantlets.

Abstract The paddy rice in the field experiment, grown at three different altitude localities, viz. Yuanjiang (north tropic type about 400 m altitude), Yuxi ( middle subtropics type about 1600 m altitude) and Dali ( north subtropics type about 2000 m altitude) in Yunnan province in 1988, had been fed with the 14C to the paddy rice to have been treated with different levels of nitrogenous fertilizer, during the booting and grain filling stage, respectively. All the samples of the aerial plant parts had been collected at the yellow ripe stage, and divided into vegetative mass (included leaves, leaf sheath, stem, ear axis and pedicel and its dieback parts) , rice and chaff, and then determined dry weight and specific activity of the 14C, respectively, and that the percentages of the 14C in each part had been calculated by dry weigth.

Abstract V. F. Brotherus had studied the bryoflora of Yunnan, Sichuan, Guizhou, Hunan and published in "Symbolae Sinicac IV" (1929) in which only two species, Ditrichum flexicaule (Schwaegr.) Hamp. and D. microcarpus Broth. are distributed from Yunnan. Recently, Cao Tong has examined the type speci-mens of D. microcarpum and treated as a synonym of D. pusillum (Hedw.)Hamp. In "Checklist of the Mosses of Yunnan Province, China" ( P. C. Wu and P. L. Redferan ed. 1984) there are 3 species and 1 variety are listed. Now the author has studied on the genus from different localities of Yunnan, in which 7 species are discussed, 3 of them: Z). brevidens Nog., D. darjeelingense Ren. et Card. and D. forfuloides Grout are new to Yunnan.

The thorny succulent thrubs in dry-hot valley of Yuanjian county are special secondary shrubs with the characters of tropical desert vegetation. The shrubs distribute mainly in the area below alt. 600 m in the valley and grow on the drier and hotter rocky banks. The succulent genera Euphorbia and Opuntia together form the upper synusia of the shrub layer of the community and other many dry-hot resistant shrub species form the lower layer. Under the several human disturbances to the natural vegetation and malpractice, cultivated Euphorbia royleana and Opuntia monacantha intruded into the semi-savanna of the valley and formed the thorny succulent shrubs. The shrubs may be accepted as an association which can be divided into two subassociations. The flora of the shrubs has direct affinity with the xeric flora of tropical Asia and is considered to have the conne-ction with Gondwana flora in its origin. With the continuation of severe human disturbance to the natural vegetation and malpractice, ecoclimate would become drier and hotter and the secondary shrubs would continuously develop in the valley.

A C. er ythrostylo Rolfe sepalis et petalis angustioribus, labello apice emarginato glabro, carinis apice inrassatis, columna praeter apicem sangu- incum alba albo-puberula differt.

Species affinis C. tachibanae, a qua hesperidio subgloboso, supericie muricato, in hesperidio substantiis pecticis multis et in cellulis guttis acidis continente differt.

Sect．Davidianae C. Y. Wu et H. Chuang, seet. nov. Scet．Elatae Fedde 1936，p．p．min，quoad C．yunnanensis franch.,C．delphinioides Fedde，C．pterygo petala Hand．－Mazz．

Similis Barleriae ventricosae Hochstett. sed foliis sublanceolatis,in ramulorum apice congestis,flore axillare non opposito differt.

Abstract The Chinese Acacia Miller taxonomy, distribution and possible floristic origin are studied. 16 species, 3 varieties including 2 new varieties ( A. delavayi var. kunmingensis C. Chen et H. Sun and A, pruinescens var. luchunensis C. Chen et H. Sun), 2 first reported species in China ( A. tonkinensis I. Nielsen and A, vie-tnamensis I. Nielsen) are presented. The Acacia species in .China are poor, which are all belong to Subgen. Aculeiferum Vassal except species A. confusa Merr. ( Su-bgen. Heterophyllum Vassal) and distribute in the southwest and south of China tro-pic and subtropic areas, especially in Yunnan, most of these are located at the northern boundary of genus Acacia. The Chinese Acacia flora came from Indo-China Penisula one which finally came from tropic Africa by India Plate running into Asia.

"Dula", a chinense herbal drug used to prevent from poisioning of the Aconitum plants, is first recorded in Chih Wu Ming Shih Thu Khao written by Wu Chi Chun. According to his description and figure, it can be only known that "Dula" belongs to the genus Aconitum, but which species it is has becomed a problem unsolved for a long time. Almost all of the climbing plants of Aconitum, such as A. bulleyanum Diets, A. delauayi Franch., A. stapfianum Hand.-Mazz., A. episcopate Levl., A. vilmorinianum Kom., A. contortum Finet et Gagnep., are named "Dula" by the native people of Yunnan. Through the field investigation and taxonomic study combined with the data of the chemical components of the plants above mentioned, it is found that the original plant of "Dula" is A. contortum Finet et Gagnep., and the other several plants are false "Dula" and must be strictly prohibited from using as "Dula".

Abstract Agropyron tsukushiense (Honda) Ohwi var. transiens (Hack.) Ohwi (2n=6x=42) from Japan and Roegneria kamoji Ohwi from China ( 2n=6x= 42) together with their artificial hybrids (2n=6x=42) were morphologically and cytologically studied to determine meiotic behaviour, fertility of the F1 hybrids and the relationship between the two parents. The F1 hybrids appeared interme-diate between the two parents and they showed very high chromosomal pairing at the MI of meiosis.