The bone size and the stages of epiphyseal fusion of the three specimens of Paleoparadoxia tabatai from the Chichibu area, Ohnohara, Hannya and Sanyama specimens were compared. From this comparison, these three specimens were classified into two groups, large and small form. In addition to this comparison, another two skeletal specimens of P. tabatai, the Izumi and Tsuyama specimens were discussed. The Izumi specimen is from Toki city, Gifu Prefecture, and the Tsuyama specimen is from Tsuyama City, Okayama Prefecture. As a result of comparison, the Tsuyama specimen was classified into the small form with the Sanyama specimen. And the Izumi specimen was classified into the large form with the Onohara and Hannya specimens. As a result of the comparison of the epiphyseal fusion stage, the small form specimens had also small body size in the mature one and the size is smaller than the large form. So, it is clear that the difference in size is not a growth change. Thus, the two groups in size seem to display sexually dimorphic characteristics. The large forms of the Ohnohara, Hannya and Izumi specimens were male, and the Sanyama and Tsuyama specimens were females. The bone size of three specimens of the large form group was very close, but the cranium of the Ohnohara specimen had no 3rd molars. Therefore, the growth of P. tabatai will stop before the 3rd molars are erupted.

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The quarry of the serpentinite used for the National Diet Building was previously thought to be Misawa, Minano-machi, but the vicinity of Kuroya, Chichibu-shi was newly identified as the quarry. Documents preserved by the bereaved family of the quarry owner as well as oral evidence from the family revealed that the mining of the serpentinite began in January, 1929, and approximately 8m² of serpentinite was shipped over the next 2 years. Interior work of the Diet Building using serpentinite was started in March, 1929, which coincides with the mining time of serpentinite in Shimoyama district in Kuroya.

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The Southern Chichibu Belt in the western Chichibu area is named the Nakatsugawa Group and has been proved to be composed of Jurassic accretionary complexes. The Nakatsugawa Group has been divided into the Ogamata, Ryokami, Nogurizawa and Ryokami-yama Chert Units in structurally ascending order. This study reports the geology of the Ryokami Unit around Shigehagi-yama in the northeast part of Otaki, Chichibu City, Saitama Prefecture, Kanto, Japan. The major lithofacies of the Ryokami Unit in the study area is sandstone and mixed or broken facies of sandstone and mudstone. Small amounts of limestone, chert and mixed facies composed of muddy matrix and sandstone, limestone, chert and greenstone blocks are also present. The thickness of the limestone bodies in the study area reach approximately 300 m, which is greater than the thickness of previously reported limestone bodies in the Ryokami Unit. The geological structure of the study area is characterised by NE-SW strikes and steep northward dips, judging from the orientation of bedding planes, the orientation of cleavage planes and the distribution of lithofacies. In the west of Shigehagi-yama, a NNE-SSW striking, steeply eastward dipping fault cuts the general geological structure. The limestone body that is distributed from the peak of Shigehagi-yama to the settlement of Ochiai is accompanied by mixed facies composed exclusively of basaltic matrix and limestone blocks. The mixed facies composed exclusively of basaltic matrix and limestone blocks was probably formed by the tectonic mixing of the boundary between basaltic rocks and limestones of a pelagic seamount.

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This paper details my present work on tree species composition and factors affecting the distribution of Betula davurica patch forest in Mt. Warabi, Okumusashi region. On a crest flat landform, the forest consisted mainly of young Betula davurica and Quercus mongolica var. grosseserrata trees, which are local dominant species. Layers of trees, subtrees, and shrubs were indistinct, and stratification was not possible. I discovered that the distribution of the Betula davurica patch forest was influenced by artificial clear cutting before 1970. The data also suggested that the forest was influenced by damage or blowdown caused by wind and soil disturbance.

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Larvae of Nothopsyche yamagataensis were studied in the mountain to middle stream of Arakawa river system in Saitama prefecture. It is a common species in mountain area at central Honshu and, the larvae are usually found abundantly in the pools of streams during late autumn and early summer. In this paper, we report additional records of this species from Saitama prefecture, and the characteristics of their habitat in the prefecture were as follows: (1) the segment is colluvial valley, (2) the reach type is step-pool, (3) the channel morphology is “Aa” type, (4) the larvae were mainly collected in the edge of eddy or plunge pools with the plentiful fallen leaves. On the other hand, another species named Nothopsyche sp. NA closely related to N. yamagataensis was collected from roots of riparian plants (ex. Phragmites spp.) exposing to the flow of river at the lateral pools of middle stream.

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The fruitfly fauna of Saitama Prefecture were assessed in taxonomy, biogeography, and species assemblages. A total of 63 species were recognized from Saitama, with additional 433 specimens identified to 54 tephritid species. Seventeen species were recorded from Saitama for the first time. The fauna of the Kanto Mountains with adjacent prefecture (Gunma, Yamanashi, and Tokyo) were reviewed and a total of 90 species were recorded from these areas. Two unidentified species of Acidiella and Philophylla were noted taxonomically. Non-metric Multidimentional Scaling based on presence-absence data of tephritid species in each municipalities of Saitama suggested that species assemblages in western mountain areas of Saitama are partly shared with eastern plain area. A path analysis was used for determining environmental factors influenced species richness among municipalities in different altitudes, population densities, and forest areas. It suggested that some municipalities in the mountain area attracting the collectors have a good number of the localities of the species records.

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