The Genus Paris L., distributed in Europe and Asia, is one of the genera of Trilliaceae. There are currently 19 recognized species. The karyological study indicates that basic number of the Paris species is X=5, and here are two kinds of the basic karyotypes: tropical type (K2n=2x=10=6m+4t), and temperate type (K2n=2x=10=6m+4st, or 6m+ 2st+2t). The species (13) with the tropical karyotype are distributed in the tropical and subtropical regions in Asia; the others with the temperate karyotype (6 species) occur in the temperate area of Eurasia. In the genus Paris, there are two peripheral species, which both have temperate karyotypes: tetraploid P. quadrifolia, in the western part of the overall range of the genus (Europe), and octaploid P. japonica, limited in the eastern part (Japan). All the species having tropical karyotypes are diploid. Among them, the more primitive ones such as P. dunniana, P. vietnamensis are concentrated in South China and the north of the Indo-China Peninsula. Examination of the geographical distribution of the species in the light of the karyological data has led the authors to propose: Paris originated in the tropical area between 18°N and 23°27’N in Asia. 14 species, which together make up 74% of the total (with 10 different karyotypes), occur in the area from the Qionglei Mountains to the Yunnan-Guizhou Plateau. With the greatest density of species in the area and their remarkable differences in chromosome ploidy and karyotypes, this region is without doubt the centre of modern distribution and differentiation of Paris.

Subfam. Panicoideae consists of 230 genera and 3000 species, about 1/3 of the total number of Gramineae. The evolution in Gramineae (Poaceae) is considered to have been proceeding in the direction of simplification. Three major lineages in Panicoideae are recognized based on analysis of characters, geographical distribution and ecological preferences. They are represented respectively by three supertribes i.e. Panicatae, Andropogonatae and Maydatae. The first supertribe has well-developed florets, fertile lemma indurate, but is awnless and thus is the primitive group in the subfamily. In the second supertribe spikelets are well-developed, the lower glume is larger than the florets and embraces them, the florets are awned. Particularly significant is the evolution of spikelets from solitary to paired, from the two spikelets of each pair both bisexual and alike in form to heterogamous pair of spikelets in which the sessile one is fertile and the pedicelled one sterile and further to homogamous pair of spikelets at base of inflorescence. In this lineage occurs an inflorescence protected by a large sheathing bract. It is the most flourishing by developed evolutionary branch. In the third supertribe raches are developed, thick, inflorescences have become pillar-shaped with spikelets sunken in the raches. The reduction of spikelets from bisexual to unisexual has taken place and they occur on separte inflorescenes, bringing about subsequent sexual differentiation of inflorescences. Raches have also evolved from solitary to united. The supertribe Maydatae is likely to be one of the most advanced group in Gramineae. Subfam. Panicoideae occurs in the tropics and subtropics, and these three supertribes have apparently followed three lines of development under different environmental conditions. The supertribe Panicatae adapts to hot moist conditions, the supertribe Andropogonatae adapts to a monsoon climate, occurring in savannas, the supertribe Maydatae occurs in monsoon moist conditions.

Czernaevia Turcz. is a monotypic genus in the Umbelliferae, tribe Peucedaneae, with the only species Cz. laevigata Turcz. occurring in northern East Asia. Although the species has often been included in Angelica L., and sometimes even in Ostericum Hoffm., the present study indicates that it is distinct not only in having dimorphic petals, but also in its fruit structure, pollen morphology and phytochemical components. The fruit has numerous, compressed vittae, the pollen grains are not constricted at the equatorial region with a small P/E ratio (1.7-2.1), and neither coumarins nor flavonoids have been found to be present at significant level in the species. It is taxonomically probably rather isolated and the monotypic genus Czernaevia is tenable.

In the present paper 8 species with 15 populations of the genus Paeonia L. (if P. papaveracea and P. japonica are recognised as species) were collected from Sichuan, Shaanxi and Hebei provinces (see the Appendix for detail of the materials). The micrographs of their somatic metaphase (also Mii in the case of P.veitchii) are shown in Plates 1-4, the karyotype formulae, ranges of chromosome length and classification of karyotypes according to Stebbins (1971) are shown in Table 5: the idiograms in Figs. 1-2, and the parameters of chromosomes in Table 1-4. The essential points are mentioned as follows: (1) Chromosomes of the various species in the section Modan have so far been examined and they are all diploid, the two species in the section Onaepia are also diploid, and thus tetraploids exist only in the section Paeonia. (2) Chromosomes in the genus Paeonia are relatively stable except for the differentiation of ploidy. The karyotypes (Table 1-4) show no differences among different taxa in Sect. Modan and the same can also be said about the taxa in Sect. Paeonia (Table 1). Not only are the karyotypes very similar, but also among the members within either section have the same parameters of chromosomes, and, differences, if occur, are not statistically significant. Between the two sections, however, the situation is different. The arm ratios of the first pairs of chromosomes in Sect. Modan are 1.53, 1.52 and 1.48 (Table 1), but those in Sect. Paeonia are 1.12-1.28 (Table 2-4), 95% confidence limits are 1.46-1.60 for the section Modan and 1.07-1.28 (1.21-1.35 only for PB85078) for the section Paeonia, not overlapping, which indicates that the two sections have differentiated in respect of the first pairs of chromosomes. (3)The population PB85024, which belongs to the P. obovata complex, has a karyotype of 2B (stebbins, 1971), which is a new one in the genus Paeonia. This karyotype is a stable one, for several individuals in the population are uniform in this respect, which shows that Stebbins’ (1971) generalization that all the species in Paeonia have 2A does not hold true. (4) Three populations of P. obovata complex studied in this work from Sichuan and Shaanxi are all tetraploids, and one from Hebei is a diploid. From the present work and the previcus reports, the materials from Japan and Korea, no matter whether flowers are pink or white, are diploids, those from Heilongjiang Province (with both pink and white flowers) (Liu Ming-yuan, personal communication) and from Heibei Province (with pink flowers) in China are also diploids, the one from Sakhalin (pink flowers) is tetraploid, those from Priamur of the Soviet Union are a tetraploid (with white flowers) and a diploid (with pink flowers), and those from Shaanxi (the Qinling Range) and western Sichuan (with both pink and white flowers) are all tetraploids. As far as we have now known, ploidy in this particular complex is correlated with the geographical distribution: diploids are found in the central part, tetraploids occur in the northern limits, and in the south letraploids are the only cytotype. (5) The materials of P. mairei from western Sichuan and Shaanxi (the Qinling Range) are found all to be tetraploids, which shows that two cytotypes, diploid and tetraploid, exist in this species, but the geographical distribution pattern of these two cytotypes is to be revealed in the future investigation.

The present paper describes the pollen morphology of Trigonobalanus doichangensis (A. Camus) Forman of Fagaceae. Comparative study on pollen grains was carried out by means of light microscope, scanning and transmission electron microscope. The pollen grains of T. doichangensis are subspheroidal or suboblate but in polar view they are subtriangular, and in equatorial view they are subcircular they are 27.3, 23.1-29.4)×27.3(25.2-29.4) μm in size and 3-colporate goniotreme. The exine is 2-layered, 2.4-4.2μm, thick in apocolpia. The sexine cosists of tectum, bacules and endonexine under TEM. On the basis of pollen shape, type of aperture and exine structure the pollen grains of T. doichangensis are distinguishable, from those of other genera in Fagaceae and it may belong to a new type of Fagaceae.

The present paper is part of taxonomic study on Chinese Phyllanthoideae. Included in it are two new varieties, Leptopus esquirolii var. villosus and Drypetes hainanensis var. longistipitata, one new combination, Glochidion triandrum var. siamense, and seven new records in China: Drypetes salicifolia, D. hoaensis. Actephila subsessilis, Glochidion khasicum, G. nubigennum, Bridelia spiosa and B. poilanei. In addition, seventeen taxon names are newly reduced: Liodendron formosanum = Drypetes formosana, Liodendron matsumurae = Drypetes matsumurae, D. longipes = D. indica, Antidesma paxii = A. acidum, A. hiiranense, A. filipes and A. pentandrum var. hiiranense = A. japonicum, A. calvescens = A. montanum, A. microphyllum = A. venosum, Breynia stipitata var. formosana and B. jormosana = B. vitis-idaea, Glochidion zeylanicum var. tomentosum = G. hirsutum, G. rubidulum = G. thomsonii, G. acuminatum = G. triandrum, G. fagifolium and Phyllanthus fagifolius = Glochidion sphaerogynum, Bridelia penangiena = B. insulana, B. henryana = B. tomentosa. All the types are kept in SCBl and PE.

A detailed description is given of the new species Archineottia japonica M. Furuse, which is the first member of the genus reported from Japan. Two specimens of this rare plant were collected by the senior author from Yamanashi and Nagano of Honshu respectively. Its habit is very similar to that of Neottia, which is represented in Japan by two species, N. papilligera (=N. nidus-avis var. manshurica) and N. asiatica (=N. acuminata), From them, however, it can be very clearly distinguished by its peculiar column on which nothing is found but a terminal stigma and one erect stamen with rather distinct filament. This is no doubt a very primitive column structure, only found in Archineottia and quite different from that in Neottia (Table l). This Japanese plant is a true Archineottia, from which it shows no difference in column structure. It is akin to A. smithiana of China, and probably also to A. pantlingii of Sikkim, all belonging to the section Furcilla. But it differs much from them by the nearly oblong lip almost equal in length to the petals. Its occurrence in central Honshu of Japan is indeed of phytogeographic interest, indicating the floristic connection of this region with central China and the Himalayas. The genus is now composed of five species. A key to them is provided as follows: l.Lip very similar to the petals, stigma antrorse. (Sect. Archineottia) 2.Sepals oblong or narrowly oblong, as broad as or slightly broader than the petals (Shanxi and Henan of China) ......................................................... A. gaudissartii (Hand.-Mzt.) S. C. Chen 2. Sepals ovate-oblong or ovate, nearly twice as broad as the petals (northwest India) ............... ....................................................................................... A. microglottis (Duthie) S. C. Chen 1.Lip bilobed at the apex, utterly different from the petals, stigma slightly curved forwards. (Sect. Furcilla) 3.Lip nearly oblong, slightly longer than or as long as the petals (Honshu of Japan) .................. ............................................................................................................ A. japonica M. Furuse 3. Lip obovate or nearly cuneate, much longer than the petals. 4.Lip obovate, horizontally spreading, free filament 1/3-1/4 as long as the column (Sichuan and Shaanxi of China) ............................................................ A. smithiana (Schltr.) S. C. Chen 4.Lip nearly cuneate, pointing upwards, free filament about 1/2 as long as the column(Sikkim) ....................................................................................... A. pantlingii (Duthie) S. C. Chen