Early Miocene (Aquitanian) larger Foraminifera are first described from the calcareous matrix of volcanic conglomerate and sandstone of the Shimizu Formation in the Shimanto Belt, Tosa Shimizu City, Ashizuri Cape, Kochi Prefecture, Shikoku. The joint occurrence of Miogypsinoides dehaartii (van der Vlerk), Spiroclypeus margaritata (Schlumberger) and Victoriella conoidea (Rutten) enables the age of the calcareous matrix of volcanic conglomerate and sandstone of the Shimizu Formation to be assigned to the Early Miocene (Aquitanian). Detailed stratigraphic studies, which were carried out in Ashizuri Cape, Tosa Shimizu City, Shikoku, show that the mudstone yielding the Late Eocene (Priabonian) larger Foraminifera described by Matsumaru and Kimura (1989) is not in the Shimizu Formation, but in the Kurusuno Formation (Myint Thein et al., 1991; Myint Thein, 1992). As such, the newly described larger Foraminifera from the Shimizu Formation indicate an age for the formation of Early Miocene (Aquitanian).

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Dark gray, thin-bedded limestones intercalated with calcareous sandstone and shale are exposed at about 3km southwest of Ban Phia, Changwat Loei, northeastern Thailand. These limestones yield well-preserved fusulinaceans which indicate a late Early Permian (late Yakhtashian) age and represent a new additional Permian fusulinacean fauna in Thailand. The following species are new to science; Darvasites ingavati, Pseudofusulina siamensis, Staffella? ovalis, Nankinella? loeiensis, and Pseudoendothyra? constricta.

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Nine species of five lophophaenid genera are described from the Lower Miocene Toyohama Formation, Morozaki Group, Aichi Prefecture and the lowest Middle Miocene Oidawara Formation, Mizunami Group, Gifu Prefecture, central Japan. A special attention is given to describing and illustrating the details of their skeletal structures which possess one or two horizontal rings, since it is believed that these details are important in establishing the taxonomy and clarifying the phylogenetic relationships. The examination discriminates seven types of skeletal structure. Four species are newly described, and two new genera, Steganocubus and Cryptogyrus, are also erected herein.

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Fossil Ginkgo is one of the index genera characterizing the Late Jurassic-Early Cretaceous Tetori-type and Siberian-type floras in Eastern Eurasia. Fossil Ginkgo leaves are sometimes crowded in occurrence, thickly massed and appressed on the same bedding plane, so representing a fossil population. One of us (Zhao) and his Chinese coworkers collected a number of detached fossil Ginkgo leaves from such an occurrence from the Xingyuan Formation (=Jiufotang Formation) at the Xilutian Open Coal-Mine, near Chifeng area, Zhaowudameng District, Inner Mongolia. These Ginkgo leaves are varied in size, form and mode of lamina-division. Nevertheless, they form a single fossil population, and thus belong to the same species, because their morphological features are similar and are thought to be within the range of variation and their cuticular features except for minor points are the same. This paper deals with the description of these leaves, with geographical and stratigraphical distributions of fossil Ginkgo leaves in the western part of Northeast China, and with generic and specific revision of some previous works and makes a brief comparison of the present population with those hitherto known. The present population of fossil Ginkgo leaves is at least the same as those of Fuxin, Shahezi, Damoguaihe and Dabao Formations in Northeast China. In the case of a small number of fossil Ginkgo leaves, it is difficult to identify them down to species so far as they do not show their unique morphological or cuticular features. The present study shows that it is difficult to assess any distinction between the genera Ginkgo and Baiera. The Ginkgo leaves comprising the present population is named by us as Ginkgo manchurica (Yabe et Oishi) Meng et Chen.

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Yokoyamaoceras jimboi Matsumoto, previously assigned to the Kossmaticeratidae, and Neopuzosia ishikawai (Jimbo), N. japonica (Spath), and N. haboroensis Matsumoto and Inoma, previously assigned to the Puzosiinae, all co-occurring in Santonian to lower Campanian deposits of the Upper Cretaceous Yezo Group in Hokkaido, Japan, and Sakhalin, Russia, are reinvestigated on the basis of many well-preserved specimens. Observations on the stratigraphic occurrence, morphological variation, and shell ontogeny show these four nominal species to be dimorphs of but a single biospecies. The first two morphospecies represent the macroconch <M>, and the latter two microconch <m> for which the earlier available name is Yokoyamaoceras ishikawai (Jimbo, 1894), which is referred to the Kossmaticeratidae. This is suggested by the mode of ontogenetic shell growth, particularly of the umbilicus. A dimorphic lineage can be traced back to certain upper Turonian-Coniacian Koss-maticeras <M> and Yokoyamaoceras <m> species. The superficial morphological resemblance between the species and Mesopuzosia spp. is mere homeomorphy.

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