Asarum mitoanum, a new species of Asarum from Goto Isls., the northwestern Kyushu District of Japan, is described and illustrated. This species is related to Asarum hexalobum(sect. Aschidasarum), especially to var. controversum in sharing the calyx-tube constricted at the throat and tessellated with longitudinal and transverse ridges on inner surface, the calyx-lobe raised rugosely at base, the style which has no exserted longer stylar-protuberance on its dorsal part, and the broadly ovate to ovate leaves. However, the new species is clearly distinguished from A. hexalobum by having the characteristic trapeziform-urceolate calyx-tube, stigma located extrorsely near the top of style, half-inferior ovary and stamens reduced to half in number.

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Swollen lignotuberous roots of Agapetes serpens, A. incurvata var. hookeri, and Vaccinium nummularia of the Ericaceae are described anatomically. They are epiphytic shrubs that grow on tree trunks in subtropical or warm-temperate mossy forests of Nepal. In the swollen roots, a great amount of the secondary xylem is occupied by large multiseriate rays, and other xylem elements are restricted to narrow strips. This basic structure is consistently observed in the three species, but several features are different between the two genera. Only in the swollen roots of Agapetes, groups of radial strands of strongly procumbent cells are interspersed between the square and upright cells of the large multiseriate rays. Xylem elements restricted in the narrow strips are vessel elements, fiber tracheids, axial parenchyma cells, and uniseriate ray cells. All the elements are small in diameter. The large multiseriate rays are composed of thin-walled and less lignified large parenchyma cells. They are produced both from widening of small-sized ray cells(initials)and from transformation of fusiform initials into ray cell initials. It is considered that the large parenchyma cells of rays function as water storage and that groups of radial strands of strongly procumbent cells function as radial transport tissue.

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Trichome micromorphology was examined by scanning electron microscopy on 29 species in all 15 genera of Celtidaceae and Ulmaceae. The two families, like other Urticales, have both clavate(or capitate), multicellular glandular trichomes and attenuate, unicellular, non-glandular trichomes. Glandular trichomes of Celtidaceae are diverse, while those of Ulmaceae are always short clavate. A surface of non-glandular trichomes is generally micropapillate in Celtidaceae(except in Ampelocera)but always smooth in Ulmaceae. Trichome micromorphology thus distinguishes Celtidaceae from Ulmaceae, and further indicates that Celtidaceae(except Ampelocera)are more similasr to other Urticales than to Ulmaceae. However, comparisons with putative outgroups of Urticales(I.e., certain orders of Hamamelididae or Dilleniidae)suggest that trichome character states shared by Celtidaceae and other Urticales are plesiomorphic, and those of Ulmaceae apomorphic. Although relationships of Celtidaceae are still uncertain, Ulmaceae seem likely to be in an evolutionary line distinct from all other Uricales. An isolated position of Ampelocera is also discussed.

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Karyomorphology in two African species of Nesaea(N. aspera and N. cordata)of Lythraceae was studied for the first time using meristematic cells of root tips. Chromosome numbers are 2n=10 in Nesaea cordata and 2n=30 in N. aspera ; 2n=10 in N. cordata is the lowest number in the genus. The two species are similar in having the simple chromocenter type at interphase and a karyotype containing chromosomes with secondary constriction.Based on the present and earlier information, we determined the chromosome base number of Nesaea to be x=5, a number derived in Lythroideae where most genera are known to have x=8. Relationships of Nesaea with several other genera with x=5(Diplusodon, Lythrum, and Peplis)are also briefly discussed.

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The pollination system of Neuwiedia veratrifolia Blume was investigated using bagging, emasculation, hand pollination tests and field observations at padang, West Sumatra, Indonesia. Many individuals within a population and in neighboring areas bloomed synchronously. Indeterminate inflorescences of 30-75 flowers daily supplied one open flower on an average(7 flowers at maximum). High seed set in bagged individuals suggests that this species is self-compatible. The evidence of high seed set from bagged individuals and the close proximity of the stigmatic area and the introrse anthers indicate that this species may be mostly self-pollinating. In addition to self-pollination, the stingless bees Trigona laeviceps and T. Sp.(Hymenoptera, Apidae)seem to act partly as pollen vectors for the species.

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Modern cultivars of edible lily bulb in Hokkaido are assumed to have been derived from a hybrid between Lilium leichtlinii Hook. fil. var. maximowiczii(Regel)Baker("a Maximowicz's lily")and Lilium lancifolium Thunb. ("a tiger lily"). They are assigned to the Maximowicz's lily, although the actual breeding process is unknown due to the lack of exact pedigree records. An analysis of RFLP of chloroplast DNA in landraces, modern cultivars, and their putative wild progenitors showed the presence of severn cpDNA haplotypes(I〜VII)in wild populations and two haplotypes(III, IV)in the cultivars of the Maximowicz's lily. A triploid species, the tiger lily, was monomorphic in cpDNA haplotype(I). It is assumed that the contributor to the modern cultivars were two landraces derived from wild populations of the Maximowicz's lily in Honshu of Japan, and that the tiger lily contributed rarely as a cytoplasmic donor.

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The RFLPs of the PCR-amplified cpDNA of seven Japanese species of Sanguisorba were investigated. Twelve restriction site mutations were phylogenetically informative. On the basis of Wagner parsimony analysis, a single most parsimonious tree with two clades was generated : one clade comprising S. albiflora, S. hakusanensis, S. japonensis, and S. stipulata, and the other comprising S. obtusa, S. officinalis, and S. tenuifolis. Morphologically, however, S. obtusa in the latter clade closely resembles the former four species of the other clade. Three possibilities are discussed to explain such a discrepancy between the species relationships supported by morphological evidence and those suggested by molecular evidence. Molecular evidence further does not support close relationship among S. albiflora, S. obtusa, and S. hakusanensis that are suggested by Nordborg earlier.

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Restriction site variations of chloroplast DNA(cpDNA)in three species of Veratrum(V. stamineum, V. album, and V. maackii)were investigated to contribute to understanding genetic variations in relation to their morphological diversity and associated taxonomic treatments. The investigation was made on the basis of individuals from 32 populations(29 from Japan, two from Korea, and one from Austria)and using eight restriction enzymes. A total of 19 restriction site mutations were identified. A parsimony analysis with these data showed that the 32 populations were divided into three distinct clades comprising the following taxa or populations : (I)Veratrum stamineum and V. album ssp. oxysepalum of central Honshu ; (II)V. album ssp. oxysepalum of Hokkaido, Chugoku-Honshu-Shikoku-Kyushu, and Korea, and V. album ssp. album of Austria ; (III)V. maackii. Although V eratrum album ssp. oxysepalum from central Honshu possesses the same cpDNA mutations as V. stamineum, the two taxa are clearly distinct from each other morphologically. Two possibilities were discussed to explain genetic affinities between Veratrum stamineum and V. album ssp. oxysepalum of central Honshu.

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For an initial step for further biological researches, mistletoes(Loranthaceae and Viscaceae)were analyzed with respect to their distribution, host trees, pollinators, and dispersers in the Kathmandu valley, Himalayas with an elevation range from 1300 m to above 2400 m. Nine species of mistletoes from 11 localities were found, including three species recorded for the first time. Seven specdies of the mistletoes were adapted to a wide range of altitude. The mistletoes grow on host trees including 46 species in 25 families of angiosperms. Two bird species Aethopyga nepalensis(Nepal Sunbird)and Dicaeum ignipectus(Mistletoe Bird of Fire Breasted Flower Pecker)were confirmed visiting flowers and fruits of the mistletoes, respectively. Two possibilities were also suggested as a major factor determing altitudinal distribution of the mistletoes : one is the distribution of host trees, and the other the distribution of birds as pollinators of seed-dispersers.

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The alpine flora of the northern slope of the Tokinskyi Stanovik Mountains(1300-2412m), southeastern Siberia was investigated and the similarities with the alpine flora of Japan and the arctic tundra flora of eastern Siberia were quantitatively analyzed. Among 278 taxa(274 species and 4 subspecies)in 136 genera and 51 families in the alpine flora of the Tokinskyi Stanovik Mountains, 73 taxa(26%)occur in the Japanese alpine flora and 154 taxa(55%)occur in the eastern Siberian arctic flora. The alpine flora of the Tokinskyi Stanovik Mountains is characterized by many arctic-alpine species of Salix and Saxifraga. The taxonomic spectrum using ten richest families and genera agrees better with the arctic flora of eastern Siberia than with the Japanese alpine flora. The Tokinskyi Stanovik Mountains occupy an important position in the migration route of arctic-alpine floras in northern Asia. The lower proportion of the ten richest families and genera in the alpine flora of Japan than those in the other two floras of eastern Siberia suggests that the Japanese alpine flora has developed under a milder climate. The high number of species in the families Poaceae, Brassicaceae, Fabaceae, and in the genus Draba is a distinct feature of the arctic tundra flora of eastern Siberia.

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However the species may be defined, it has neither a structural organization defined by all its members nor a function to integrate them. There is no absolute and universal factor to substantiate the grouping of individuals into a species. There are only individuals, and no framework of species exists in nature. In this sense, it can be said that the species has no reality. All of the taxonomic categories, including species, are nothing but categories, since these are human concepts and there is nothing in nature to verify their actual existence. The species is neither a natural unit, nor an evolutionary unit. Even so, there is no doubt that in nature there are distinct assemblages of individuals(in terms of similarity of their attributes). These assemblages of individuals are categorized into what we call species according to their attributes. In this sense, the species may be said to exist, as do other taxa in the taxonomic hierarchy also. In this case, too, what exists are only groups of individuals, and these have nothing to certify themselves as belonging to species, as mentioned above. There are no essential differences between species and other taxa in the taxonomic hierarchy. In this paper, the species is defined as follows : a species is a group of individuals similar in attributes and differing distinctly in taxonomically important characters from other such groups. In this definition 'similar'must be homologous, and 'taxonomically important characters'should be considered for each particular case. This definition is believed to accord well with the so-called taxonomic species concept which seems to have been most widely accepted. Species should be delimited based on the similarity in attributes possessed by the individuals. For this delimitation, we need to conduct a synthetic study and take into account various aspects of organisms. Delimitation of species by a single criterion, such as reproductive isolation, is inadequate. In this paper, I also explain why Mayr's definition of a species is inadequate, and I counter his criticisms towards the nominalistic recognition of species.

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Pollination mechanisms in conifers are diversified and generally correspond with taxonomic boundaries. In Tsuga, Hesperopeuce(Pinaceae), Saxegothaea(Podocarpaceae)and Araucariaceae pollen germinates outside the ovule and a long pollen tube penetrates the micropyle. In the remaining genera so far examined in conifers, pollen is captured by ovules and germinates in the micropylar canal. The pollen capture by ovules usually involves a pollination drop secreted from the ovule Non-saccate pollen in Cephalotaxaceae, Cupressaceae, Sciadopityaceae, Taxaceae and Taxodiaceae lands on a pollination drop. It simply sinks in the drop and reaches the nucellus if ovules are erect, or it moves upward carried by the meniscus of the drop if ovules are inverted. Since the nucellar apex is hydrophilic and the inner surface of the integument is hydrophobic, the meniscus of the pollintion drop moves upward when it recedes in the micropylar canal of the inverted ovules. Saccate pollen of Picea, Pinus(Pinaceae)and most genera of Podocarpaceae is also captured by a pollination drop. In these genera ovules are inverted, and pollen in contact with the drop floats upward to the micropyle and subsequently carried into the micropylar canal perhaps by the drop meniscus. In Cedrus rain water, instead of a pollination drop, is the main vehicle for pollen movement to the nucellus, and this may be also true in Picea and Pinus. In Larix and Pseudotsuga(Pinaceae)pollen adheres to the integument tip, and it is carried into the micropylar canal when the tip invaginates into the canal. Our knowledge on the pollination mechanisms in conifers thus far is based on about half of the extant genera. Clearly research efforts should be concentrated on the mechanisms in the remaining genera and poorly examined genera. Available literature suggests further intensive studies in such aspects as the chemical composition of the pollination drop, mechanisms of secretion and receding of the drop and the relation between pollen size and pollen movement in the micropylar canal. These studies would provide insight into evolutionary considerations and essential information for seed production which often limits reforestation programs in conifers.

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The Kuril Islands are an attractive field site for investigations of the phytogeography and island biology. Earlier plant collectors and references of floristic and vegetational studies on the Kuril Islands were tabulated to provide information sources for future studies. Poor level of botanical knowledge on northern parts of the middle Kurils was also discussed.

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