Floral and reproductive characters were examined to determine mode of dimorphism in the flowers of Psychotria boninensis Nakai, a species endemic to the Bonin (Ogasawara) Islands, Japan. The flowers reciprocally differed in stigma and anther height, and were composed of long- and short-styled morphs. Pollen grains from the short-styled morph were larger than those from the long-styled morph in size, but no major difference was found between the two morphs in exine sculpture. The short-styled flowers produced less pollen grain than the long-styled flowers, as in some other typically distylous species. The pollen grains produced by the two morphs were positively stained with Cotton Blue solution, and ovaries of the two morphs produced fruits and seeds in field. These results suggest that the flowers of P. boninensis are morphologically distylous, as in most of the typically distylous species, and that the long- and short-styled flowers are functionally bisexual. This is the first record of distyly among the plants endemic to the Bonin Islands.

A new species of Saussurea (Asteraceae), S. kubotae Kadota, is described from the Taishaku-dai limestone area, Hiroshima Prefecture, western Japan. Saussurea kubotae is morphologically similar to S. tanakae Franch. & Sav. ex Maxim., however, the former is different from the latter by having 13-seriate involucral phyllaries, a loose terminal raceme with longer, divaricate, scaly peduncles, obovoid involucres, sagittate lower cauline leaves, longer anthers and larger achenes. Sympatric occurrence of S. kubotae and S. tanakae was observed in the Taishaku-dai limestone area but any intermediate forms between the species were not found.

In the course of floristic research of Myanmar, some noteworthy monocots; Aponogeton lakhonensis A. Camus (Aponogetonaceae), Cryptocoryne cruddasiana Prain, C. crispatula Engler var. balansae (Gagnep.) N. Jacobsen (Araceae), Stichoneuron membranaceum Hook. f. (Stemonaceae), were collected. Of these Cryptocoryne cruddasiana, endemic to upper Myanmar, was recollected in Kachin State (the northernmost state in the country) after an interval of more than half a century. Other taxa are new to the flora of Myanmar. These materials may also be significant in clarifying the floristic elements of Myanmar and their relationship with those of neighboring regions.

We report here new species of Silene L. (Caryophyllaceae) from the Sino-Himalayan region. They are three new species, S. hideakiohbae Rajbh. & Mitsuo Suzuki, S. davidlongae Rajbh. & Mitsuo Suzuki and S. greywilsonii Rajbh. & Mitsuo Suzuki, from Nepal and one new species, S. akiyamae Rajbh. & Mitsuo Suzuki, from China.

The genus Saxifraga is highly diverse in the Sino-Himalayan region, and our taxonomic knowledge of the group is still insufficient. This is the first of a series of papers concerning the taxonomy of Saxifraga, and deals with 1) the delimitation of section Ciliatae series Lychnitideae (Engl. & Irmsch.) Gornall and 2) S. excellens Harry Sm. and similar species. 1) Saxifraga series Lychnitideae consists of four species, S. lychnitis Hook. f. & Thomson, S. nigroglandulifera N. P. Balakr., S. pseudohirculus Engl., and S. viscidula Hook. f. & Thomson. A new combination S. lychnitis var. oresbia (J. Anthony) S. Akiyama & H. Ohba is proposed. 2) Three species with reddish or reddish purple petals of Saxifraga section Ciliatae are compared. Saxifraga bergenioides C. Marquand differs from S. excellens Harry Sm. and S. pardanthina Hand.-Mazz. in having pedicels and sepals with brownish curled hairs against those with short, black tipped glandular hairs of the two other species. Saxifraga pardanthina differs from S. excellens mainly by the spotted petals with cordate base and reflexed sepals. A recent collection of S. excellens, endemic to Nepal and known only from a few specimens, allowed us to observe and illustrate it in detail.

The tropical and subtropical marine diatom taxon Perissonoë crucifera (Kitton) Desikachary & al., was obtained from the coast of Iriomote Island, Okinawa Pref., for the first time from Japan. Frustule is quadrate in valve view, composed of two valves, a valvocopula and a pleura. Each valvocopula and pleura comprises four quarter bands (QBV and QBP) with four corner bands (CBV and CBP) covering the openings between QBs. CBP extends along the bottom sides of two pleurae. Granules are scattered over the outer surface of a valve. In a mantle, many granules and small areolae are alternately arranged in a line. On both surfaces of a QB, areolae are arranged in a single line like those on a valve. Areolae on a valve and mantle are occluded by concentric rotae and are supported by two to four spokes. In the apical pore fields, there are smaller areolae perforated by rota-like segments.