Mature fruit wall structures and chromosome morphology were investigated for all seven species of Crepidiastrum and five species of Paraixeris (Compositae-Lactuceae). Two genera had 10-20 obtuse costae in the transverse section of the fruit, of which five were much thicker than the remainder. Furthermore, the two genera examined agreed with each other in having basically the same costa structures, i.e., 1) sclereid-fibers lacing between the exocarp and the underlying libriform fibers, 2) libriform fiber cells occupying nearly the whole costa, and under lying fiber-sclereid tissue being only 1-3 cell layers thick, and 3) intercosta lacking fiber-sclereid layers. The chromosome morphologies of all seven species of Crepidiastrum and four species of Paraixeris were also investigated. Somatic chromosome numbers and karyotypes of Paraixeris chelidonifolia (2n=10) and P. yoshinoi (2n=10) were reported for the first time. The results of the present study clearly revealed that plants of these two genera are very similar in chromosomal characters: 1) all species are diploid (2n=10) with the same basic number of x=5; 2) the type of resting nuclei is prochromosome type; 3) they have nearly the same total genome length, i.e., 22.3μm-37.1μm in Crepidiastrum and 24.9μm-34.6μm in Paraixeris; 4) the length of each chromosome also falls in a similar size range, i.e., 1.5μm-4.6μm in Crepidiastrum and 1.7μm-4.0μm, in Paraixeris; 5) they possess the same basic karyotype complement, i.e., 2sm+3st, with the one exception of C. ameristophyllum; and 6) they have a characteristic chromosome pair (No. 1) with a secondary constriction at the distal portion of the short arms (with the one exception of P. sonchifolia). Two genera also have many additional common gross morphological features: inner and outer bracts, pappus, and flowering habit. In conclusion, the overall similarity in chromosome morphology as well as fruit wall anatomy of Crepidiastrum and Paraixeris clearly indicates that they belong to a distinct phylogenetic group among the Crepis-series (JEFFERY, 1966). considering all these common characters of Crepidiastrum and Paraixeris, these two genera should be united and referred to a single genus, i. e., Crepidastrum.

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Mosses of Seram and Ambon Islands were reported based on our collections of the botanical expedition to the islands. This paper was the third part of our report on the moss flora of the islands. It included Rhizogoniaceae (four genera and six species), Racopilaceae (2-4), Pterobryaceae (6-8), Trachylomataceae (1-1), and Garovagliaceae (1-8). One new species, Powellia macromitrioides H. AKIYAMA was reported.

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Diatom genus Mastogloia from brackish Lake Shinji and Lake Nakaumi in the San'in district were described. Only two forms, Mastogloia exigua LEWIS and M. pumila (GRUN.) CL. were observed. M. exigua had a wide range of variation. The shape of central area and lateral line were not static characters of M. exigua. M. paludium VOIGT, M. pseudexigua CHOLN. and M. pumila var. lanceolata FRENG. are included in a range of variation of M. exigua, and they are synonyms of M. exigua. In a sample about 58% cells of M. pumila showed a heteropolarity. The distribution of M. exigua and M. pumila was confined to the northwest side of Lake Nakaumi.

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One species of Acrostichum and 23 species of Pteris are recorded from Seram Island and Ambon Island, the Moluccas. These include three new species, Pt. tarandus, Pt. tarandus, Pt. lepidopoda, and Pt. pediformis, one new subspecies, Pt. mertensioides ssp. polylepis, and a new combination for Pt. zippelii. A key to the local species of Pteris is provided, and collections are cited for each species. Notes are given for taxonomically and/or biogeographically interesting species.

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This is the continuation of Compositae asiaticae 3 in Acta Phytotax. Geobot. 41: 77-92 (1990). In this report, the writer treats mainly Ainsliaea, Carpesium, Cirsium, Dendranthema, etc. It is interesting that Cirsium japonicum, Leontopodium japonicum and Saussurea japonica are not yet found in Yunnan, while they are found in the middle and the north China and eastern to Japan. Such species are numerous, though there are many species common to Yunnan and Japan. Between Yunnan, Western Szechwan, Western Kweichow and Eastern Szechwan, Easter Kweichow, there is a botanical distributional border, as already known. This border is recognized also in this report.

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Life cycle of six species of Utricularia was studied in the Kinki District, southwestern Japan, with special reference to their reproductive biology. Field observations and some pollination experiments revealed that failure of sexual reproduction or development of inbreeding system seemed to be widespread in aquatic Utricularia species. The fruits did not develop in U. vulgaris var. japonica because of abnormal formation of embryo sac and high percentage of abortive pollen. U.tenuicaulis was proved to be an out-breeder, but the seed set was not good in field probably due to the absence of effective pollinators. In addition, male sterility occurred in some populations of the species, resulting in a failure of sexual reproduction. In U. minor flowering was not observed during the study period. U. dimorphantha had cleistogamous (CL) as well as chasmogamous (CH) flowers and CL flowers played much greater role in its speed production than CH flowers. The populations of above four species were maintained vegetatively by turions. To the contrary, U. aurea and U. exoleta, both of which did not have turions as a means of vegetative reproduction, were shown to produce seeds efficiently by self-pollination. The position of their stigma and anthers facing to each other at dehiscence promoted the self-pollination.

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