Plant taxonomists traditionally place a heayy reliance on floral charactess in assessing relationships and in arriving at taxonomic conclusions. From the standpoint of reproductive biology, differences in number, shape and position of floral parts, in perianth-color patterns, and in various phenological traits, are all features that represent adaptations to various modes of pollination. Such an awareness can immeasurably aid the plant taxonomists in making intelli-gent taxonomic assessments.

The conditions of somatic embryogenesis in cothledon culture of Camellia chrysantha(Hu) Tuyama were studied.The embryoids were occurred on the Murashige and Skoog medium with the addition of 6-benzyladenine or combination with NAA.Histological observations showed that the embryoids originated from the epidermal cells of cotyledon.The root growth and the shoor development of embryoids were promoted markedly in the MS or B5 liquid medium wupplemented with cytokinin and auxin by shake culture.

The pollen of P.yunnanensis is shed at the four celled stage in March. The pollen germinated at the top of nucellar tissue, then the pollen tube grew into thc nucellar tissue and the tube nucleus into the pollen tube. In the second year, the resting pollen tube revives its activity in the nucellus towards the March. The two unequal male gamete formed in the April. Surro-unding the male nuclei some starch grains were observed. The pollen incubated in the medium containing sucrose grew much slower than that in BKBM-WS.The pollen tube and pollen grains contained abundent starch grains.

During the course of our studies on the biologically active consti-tuents of Rabdosia plants, we examined the etrereal extract of the leaves of Rabdosia bulleyana (Diels) Hara collected in the Cangshan Mountain, Yunnan, China. A new diterpenoid having a ent-Kaurene-skeleton, bulleyanin, was isolated. Its yield is 0.4% of the leaves and it shows tumor-inhibitor activities for S-180, ECA, and etc. of mice. The structure of the new compound was elucidated by spectroscopic and chemical evidences as follows; bulleyanin, mp 240-244℃, C28H38O10, ent-12β-hydroxy-1α, 3α, 7β, 14α-tetraacetoxy-16- Kauren-15-one (I ). 1H NMR data of bulleyanin and its derivatives, 13C NMR data of bulleyanin and dehydrobulleyanin have been assigned. 13C NMR assignments are based on a combination of proton noise decoupling, off-resonance decoupling and com-parison with related compounds.

From the following facts it follow that the Qing-Zang plateau Began ro elevate since the Tertiary.From the viewpoint of the area where we discovered the plants. We have a survey of the Polytrichaceae in Tibet mainly distributed in SE.Tibet and S>Tibet.This area is just along the valley of the Yalu Tsangpo(Yalu Tsangpo River).According to the theory of the continental drift,this area may well be the seam where the northern edge of the India Plate and the southern edge of the elements of Asia meet.Thus the plants of this area include not only the elements of Laurasia,but also those of Gondwanaland.As a result of this,this plants os this area characteristic if complexity of elements and greatness of species.It is because of the creash of the India plate and the continent of Asia that the Qinghai-Xiang(Chinghai-Tibet) area is uplifed by the impact of the crash.

Affinis J.rederiano Kob.,sed foliis utrinque glabris, pedicellis brevibus differt.Frutex scandens,1-2 m altus.Rami teretes,pubescentes tenuiter striati.Folia opposita simplicia subcoriacea,obovata vel elliptica interdum rotundata,1-1.5 cm longa,0.8-1cm alta,apice rotundata mucronata vel retusa,basi cuneata,supra viridia subtus pallidiora utrinque glabra.

Species similis B.strictae(L.f.) G.F.W.Mey sed floribus axi11aribus solitariis rubellis,staminibus inclusis differt.Herba annua. Caulis erectus vel ascendens 10-30 cm altus, ramosus,subtetragonus, puberulus. Folia chartacea opposita lineari-lanceolata, 2- 4 cm longa 3- 5 mm lata, apice acuminta, margine revoluta, utrinque scabrosa,costa supra impressa subtus prominula, stipulae cum petiolo connatae apice truncatae fulvido-echinatae.

Species C.glaucae(Thunb.)Oersted affinis,sed foliis aristato-serratis,subtus crassiorius a1bo-farinoso-stratis,et pilis villosis adpressis obtectis,nervis 1ateralibus utrinque(7-)9-11;cupulis lamellis concentricis 5,integris facile differt.

Species affinis Rh.procumbenti Edgew.et Rh.bodinieri Levl., sed foliis minoribus,apice obtusis vel rotundatis, margine integris vel tantutm ad apicem minute serratis 1-3, petiolis 2-3 mm longis, f1oribus 2-3 in axillis fo1iorum confertis, pedicellis brevioribus circ. 2 mm 1ongis, seminibus dorso sulco inferne latiore, superne angustiore aperto instructis differt.

Yuanjiang valley is one of the most dry-hot areas in Yunnan Province. Savanna is distributed in mountains under the altitute of 800-900 meter widely.According to the Local Records of Yuanjiang County Printed in 1714, 1826 and 1922, and through our exploring to present-day vegetation,the authors give a brief view of vegetational change in Yuanjiang dry-hot mountains in the last 500 years.The paper presents that the forest cover degrees in the county were declined by increasing human population, it shows a progressive change from 75 percent in the county before the midle of 17th centry, then around 70 percent during the 18th and 19th centries, then 61.5 percent in 1958, then 27.3 percent in 1975 and finally 19.3 percent in 1982. The study shows that the main plant communities in the mountains were tropical monsoon forests even seasonal rainforest before later of the 19th centry, then the savanna was spreaded quickly.

Yunnan is a province rich in flora. There are about 13,000 species of 1,984 genera alnong 240 families (230 families of Angiospermae according to Hutchin- sonts system and 10 families of Gymnospermae) in Yunnan. The number of family in Yunnan is about 79.73% of 301 families in China, the number of genera 64.8896 of 3,058 genera in China, and the number of species 52% of 25,000 species in China. The four very big families such as Orchidaceae, Compositae, Papilionaceae and Gramineae which contains 10,000 or more species in world- wide separately, all have a lot of species in Yunnan.